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Flattened primers
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I know there has been much discussed concerning the reasons and remedies for flattened primers, because I've read most of them on more than one forum, but I can't seem to derive a remedy for mine without eliminating a number of variables, which I'm willing to do, but choosing which change that's the most likely to help,(which course of action first) I could use a little help with. The rifle is an old sporterized M98 I picked up at a gun show some time back and I've gone through it completely. It's head spacing was terrible so the barrel was pulled and lathed and set back properly until it head spaced correctly, lugs were great and FP protrusion is good. I did a chamber casting and found the lead a little long though. I loaded up some once fired cases with IMR 4895 and picked a middle of the road 47gr according to a Lyman manual and used some 165gr spbt bullets pushed by Winchester primers. I usually use Fed 210's but had these lying around and wanted to use them up. There brass primers and maybe there softer than the Federals I don't know. My OAL on these cartridges was dead on at 3.30. I blacked a bullet on one and chambered it to see where my lands made contact and found no marks but I don't know if I can stretch the length any or not. I don't know if I should try changing primers first, or back down the load some, or lengthen the the OAL. My only other powder I have at this time is Win 760 but the book shows it burning with higher pressure. Any help out there? Thanks!
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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What chambering does this rifle have?


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Posts: 7360 | Location: South East Missouri | Registered: 23 November 2005Reply With Quote
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What's wrong with flattened primers? Are there any signs of high pressure? Cratered? Pierced? Case head expansion? Loose primer pockets?

I assume we are talking 30/06.
 
Posts: 1082 | Location: MidWest USA  | Registered: 27 April 2013Reply With Quote
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Yes sorry, it's a 30-06. No other signs of high pressure other than the flattened primers, zero growth on head expansion. All primer pockets were trued to depth and flash holes deburred. When I primed the pockets they didn't feel tight but but none fell out either, it's hard to tell as I use a ram prime to install the primers. Primers sat just a hair below level with case head and all primed uniformly.
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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All primers are brass. The silver ones are nickel plated but are still made of brass.
How flat is flat?
How many loads can you get before the primes are no longer tight?
Flat primers are not necessarily a sign of high pressure. Soft primers cause it too.
All these questions, and more, need to be answered before anyone can determine if there is a problem.
 
Posts: 17046 | Location: USA | Registered: 02 August 2009Reply With Quote
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The whole "flattened primer" thing came about by using CONVEX primers.
IOW the primers you are using are FLAT to start with, so all you can judge is the amount of "squaring" around the edge.

Now, when the firing pin hits the primer, it jams the case fully forward in the chamber before it lights the primer. As pressure builds it pushes the primer back against the bolt face before expanding the case against the chamber walls. As it continues to build it stretches the case back against the bolt face, re-seating the primer. Up until than the primer corner is unsupported.



The primer on the left is from a factory load, middle from a book max load and on the right is a overload.
 
Posts: 2124 | Location: Whittemore, MI, USA | Registered: 07 March 2002Reply With Quote
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My first guess is enlarged primer pockets. have you tried the load using cases w/o the primer pockets altered?
Primer appearance is one of the least reliable signs of pressure. And it needs to be conjoined with other signs to be meaningful.


Aim for the exit hole
 
Posts: 4348 | Location: middle tenn | Registered: 09 December 2009Reply With Quote
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Side by side of the installed fresh primers, and the fired rounds.
I popped out one of the flattened primers and it looks exactly like the center primer example, Flattened with a rim top and the three anvil prongs sticking out the bottom.
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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I see no problems

Rock on


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Posts: 7360 | Location: South East Missouri | Registered: 23 November 2005Reply With Quote
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Wes62, fired primers with my own 30.06 reloads look exactly like yours, and the centre example in the primer photo. Generally my loads are probably just on max, or slightly under. Typically I get 10 + loads per case ( Norma ) before getting case breakdown issues. IMO I don't think you are experiencing excessive pressures with your load.


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Posts: 1994 | Location: New Zealand's North Island | Registered: 13 November 2014Reply With Quote
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Thanks for the input. I was looking around and found the Nosler reloading sight which indicates that 47gr is just under what they list as max load, with 44gr as most accurate(using there components),. For some reason I feel more comfortable with there data than I do on other sights. With this combination of components there seem to be a great many data variations using IMR 4895 with other sights listing there stating loads as the same as others max loads, whats a guy to do? I'm going to back down to 45gr or even 44gr and see how they perform. Thanks for all the input so far, I'm not expecting and end to this learning, it's more of a never ending journey, so more input is really welcome.
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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44g of 4895 should be a decent load.
I load a bit lighter for my Garand, but 44 should do fine in a bolt gun.


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Posts: 7503 | Location: Texas Hill Country | Registered: 15 October 2013Reply With Quote
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Reminds me of my CCI400's in an AR, the primers are a little to soft for load. When punched out they do not have a ridge just a sharp corner. If yours don't a ridge just a sharp corner I wouldn't sweat it.


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Posts: 1254 | Location: Norfolk, Va | Registered: 27 December 2003Reply With Quote
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oldIn tail gunner's photo:
the middle primer gives the appearance of reasonable pressure and possibly too much head space.

The primer on the right has a severe mushroom , darkened metal and shortened primer height indicating high temperature and presure, and meaningful metal flow.


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Posts: 10226 | Location: Temple City CA | Registered: 29 April 2003Reply With Quote
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I wouldn't even consider your examples "flattened".


Aim for the exit hole
 
Posts: 4348 | Location: middle tenn | Registered: 09 December 2009Reply With Quote
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You have no problem; drive on.
 
Posts: 17046 | Location: USA | Registered: 02 August 2009Reply With Quote
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Your rifle may now be headspaced correctly but you may be creating headspace by setting back the shoulder on your cases when they are resized. I am presuming you are FL resizing the cases.

Although flattened primers are often okay in the absence of other pressure signs, with a properly headspaced case I would be thinking a little about the load if seeing primers flattened to the extent you show in your photos, unless your case shoulders have been set back which can be corrected. If the primers when removed from the case look like the centre primer in Tailgunners photo then the pressure is high or your case is not headspaced correctly, you do not normally expect to see a top hat profile on a primer from a normal load.

Then if there are no other pressure signs, the Mauser action does not have a plunger type ejector in the bolt face which will show up on the case head with higher pressure loads, I would be happy enough using that load, remember though that Dupont IMR4895 is not a temperature insensitive powder so that load if showing those signs in cooler temperatures may well start and present other high pressure signs (sticky bolt lift) if fired during hot weather.
 
Posts: 3827 | Location: Nelson, New Zealand | Registered: 03 August 2009Reply With Quote
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Thanks for the input. The cases used are some once fired acquisitions which would not drop into the chamber at all, so they were FL resized and then trimmed, they will be neck sized only after this point. I pulled the remaining loads from this batch and reloaded them to 44.5gr, and weather permitting,will test this new recipe today.
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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Primers are unreliable for reading pressure. One issue you may be experiencing is false indications of pressure, that is flat primers, due to friction between case and chamber.

Varmit Al's page is worth looking at, what you see is upon ignition, the primer backs out of the pocket. Then as pressure builds up, the case stretches, and I mean stretches, to the bolt face and stuffs the primer back in. The case stretches because of friction between a dry case and a dry chamber. The front of a dry case will adhere the chamber and the primer backs out to the bolt face. Pressure builds and when it is high enough to stretch the case sidewalls the cartridge base backs out to the bolt face pushing the primer into the pocket. However, since the stretching takes time and elevated pressures, the primer will be expanded or expanding before it is stuffed in the pocket. Thus, flattened primers at low pressures.

This is a rare situation, where primers back out and the case sidewalls do not stretch. The load here was a 150 SMK 47.5 grs IMR 4895 mixed military cases, fired in a SAKO 30-06 rifle. The primers have backed out and the pressures were low enough, the case did not stretch to the bolt face.




You can see all of this in a computer simulation at Varmit Al's web page.
Rifle Chamber Finish & Friction Effects
http://www.varmintal.com/a243z.htm

So here is what I do. I found that by lubricating my 308 Win cases, I could shoot the things in my M1a twenty or more times without case head separations. The usual advice is to toss the things after five firings because for dry cases fired in dry chambers, the case heads come off. Obviously my case life was four times better, and I only quit because primer pockets were getting large. One thing I noticed, with lubricated cases my primers came out rounded, but with dry cases, they were flat for the same load! I figured out that the lubricated cases were sliding to the bolt face, not stretching on the sidewalls, and that the primer was either not extending out of the pocket, or was being shoved back into the pocket before it could expand.

Since then, for load development, I leave case lube, oil, grease, (Mink shoe wax!) on cases during load development. I usually see the transition from rounded to flat. Somewhere around that transition, I have hit a maximum load. This is not 100%, I have had loads that were obviously over pressure, because the primer pockets expanded, and the primers did not look bad at all. But most of the time, when I see flattened primers on lubricated cases, I am at, or have exceeded, a maximum load. Trying to evaluate primers with dry cases and dry chambers is basically folly, in my opinion.

Infallible evidence of excessive pressures is leaking primers, pierced primers, and blown primers. Regardless of whatever the reloading manual says, or friends, or people on the internet, if the load produces leaking, pierced, or blown primers, then the load is over pressure for that firearm. And you have to cut it.
 
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Posts: 1102 | Location: Denmark | Registered: 15 October 2001Reply With Quote
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Flat primers in themselves don't mean much, as the metal they use is not consistent, some is soft and some is hard, according to batch..

But do not ignore them totally, and watch for cratering primers, black soot around the primer, backed out primers, severely flat primers that void any space or crease between it and the case, add anyone of these to what you refer to as a flat primer, and you should back off a grain or two..

Primers are only a indication of pressure but when comapared with such things as sticky bolts, a crack as opposed to a bang, or a line in the head of the case, all indications or pressure, then when reloading said case when a primer flops in with no pressure that means your primer pocket expanded and that's an indication of excessive pressure...Use all these examples as indications and when you get more than one its time to back off and in some cases such as sticky bolts its time to back off...better to back off than to ignore pressure signs in many cases but not all..the advent of the chronograph is probably the most useful tool available to the handloader, we have


Ray Atkinson
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Posts: 41763 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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Does not look like a problem to me.
 
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I'd keep track of number of reloads per case batch before assigning what your spent primers look like to the problem category. Some just look different than others. (You've gotten lots of good input and I'd not worry either.)

Sometimes even harder bolt lift isn't due to pressure per se -- can be the brass is soft and/or something on extraction is shaving the head rather than it being brass flow due to over-pressure as an example of variance.

2 cents


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Posts: 4848 | Location: Clute, Texas | Registered: 12 January 2005Reply With Quote
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I pulled the loads and remeasured to 44.5 grains and went out to the range with the 17 remaining loads. Reduced recoil was real obvious and re-calibrating the scope was a breeze as the hits were much more consistent, the primers were only about half as deformed (squashed/flattened). So I think that for now I'll consider this good for my elk rifle and save the better fine tuning for when the temp gets above 5 below. Thanks for all the input everyone.
 
Posts: 133 | Location: Thermopolis, WY | Registered: 29 October 2013Reply With Quote
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quote:
Originally posted by Wes62:
I pulled the loads and remeasured to 44.5 grains and went out to the range with the 17 remaining loads. Reduced recoil was real obvious and re-calibrating the scope was a breeze as the hits were much more consistent, the primers were only about half as deformed (squashed/flattened). So I think that for now I'll consider this good for my elk rifle and save the better fine tuning for when the temp gets above 5 below. Thanks for all the input everyone.


Sounds a good outcome Wes. Your cases will now be fireformed to your chamber so just neck sizing or partial FL sizing just to kiss the case shoulder will allow you to load up to suit your rifle without the excessive flattening of primers or at least a better read of the primers as pressure rises.
 
Posts: 3827 | Location: Nelson, New Zealand | Registered: 03 August 2009Reply With Quote
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Slamfire,
I agree with most of what you said, but I don't agree with lubricating cases to fire in a rifle. I believe a case should be dry as a bone so that it can grab the chamber walls..This has been pretty common knowledge for ions, in that it prevents setback of which your claiming the opposite. I have not seen anything in print or from anyone other than you to the contrary, but that said I'm certainly interested in your reasoning as to why you believe lubricating a case releaves chamber pressure!


Ray Atkinson
Atkinson Hunting Adventures
10 Ward Lane,
Filer, Idaho, 83328
208-731-4120

rayatkinsonhunting@gmail.com
 
Posts: 41763 | Location: Twin Falls, Idaho | Registered: 04 June 2000Reply With Quote
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quote:
I'm certainly interested in your reasoning as to why you believe lubricating a case releaves chamber pressure!


I really tried to make it clear, lubricated cases do not relieve chamber pressure, at least not significantly. Grease or oil might slightly reduce chamber pressures, and this is tentative, because oil or grease on the case will be squeezed up into the chamber throat, reducing friction between bullet and barrel. This has not been tested enough to really prove that point. This chart comes from an Army cover-up, I don’t want to get into that cover-up right now, but this data was useful. They fired heavily oiled cases and it did not increase chamber pressures.



The accepted evidence of high pressures, that is flattened primers with dry cases, when I lubricated the cases, the primers came out rounded. Obviously, very obviously, rubbing oil or grease on the outside of the case is not going to change the pressures inside the case. Nor will rubbing the outside of the barrel with grease or oil increase or decrease pressures inside the chamber.


quote:
I agree with most of what you said, but I don't agree with lubricating cases to fire in a rifle. I believe a case should be dry as a bone so that it can grab the chamber walls..This has been pretty common knowledge for ions, in that it prevents setback of which your claiming the opposite. I have not seen anything in print or from anyone other than you to the contrary….


The concept that grease or oil on the cartridge creates a dangerous condition is an interesting case of the fallacy of “argument from authority”. After reviewing all the information I can find , I am of the opinion that this was originally created by the US Army Ordnance Department to hide and misdirect failures from the population of 1 million “low number” M1903’s. These rifles were made at Army Arsenals and as the designer and manufacturer, any inherent problems with rifle, in the hands of civilians or Navy and Marine personnel, were the responsibility of the US Army. The Army also wanted competitors to stop greasing their bullets. At the time the Army was loaning out rifles to Gun Clubs and to competitors at the National Matches. Eliminating greased bullets would eliminate the risk of dirt getting on the grease and scratching the chambers/barrels of their loaner rifles. The idea that greased bullets or greased cases creates a dangerous condition would have died decades ago if it had not been in the 1947 book “ Hatcher’s Notebook” . Hatcher’s Notebook is the ground zero for all the concerns expressed in the American shooting community about greased bullets, oiled bullets, lubricated bullets, lubricated cases, oiled cases. Townsend Whelen is the man actually responsible for creating the data set that the Army and Hatcher used to claim dangerous pressure increases. These men are revered by the American shooting community. Given the statue of Hatcher and Townsend Whelen (recently called “Mr Rifleman” or “the Dean of Riflemen”) within the shooting community, and the decades spanning their unchallenged claims that grease (and/or oil) dangerously raised pressures, it is no wonder that the shooting community is thoroughly indoctrinated with this belief. It is however, fallacious.

The only real problem I have, since the participants are all dead, particularly General Hatcher, is the extent to which they themselves believed this, in spite of all the evidence they had to have seen which contradicted what they were telling the American public. General Hatcher is a most peculiar case and the strong reverence for General Hatcher is such that by claiming he is not infallible, in fact, is quite fallible, will result in strong and vicious push back from his fan base.

When authority is considered so highly that no one dares or cares to challenge them, when these same Authorities are wrong, they can cause amazing damage and delay progress within society. It is very human to appeal to authorities, and since no one can know everything about everything, at some point we all rely on experts. But time has shown again and again, experts are not infallible or inerrant, they have their bias, their knowledge gaps. No matter how high a pedestal they are put on, eventually they are shown to be imperfect humans.

I think it is totally amazing that Hatcher writes what he does and yet he was the Head of Ordnance during WW2. He had access to the interiority of the Ordnance military industrial complex. He had authority over all the test labs, test facilities, even equipment manufacturers, which is why of course, why his authority is so high among the shooting community. We don’t know all of what Hatcher knew. He is a primary source on single heat treat 03’s, the blow up lists, the development of the Garand, his Textbook of Firearms Identification and Evidence was a primary forensic source for law enforcement. In so many instances Hatcher is the sole and primary source. And yet, knowing what he actually did know, knowing what his associates knew, knowing what he therefore should have known, I find his section on greased bullets and the tin can ammunition extraordinary. How could he not have known that what he was writing was bunk? I waffle between believing that Hatcher knew it was a cover up, but, based on readings elsewhere, I am discovering that the human capacity for self deception is infinite, so maybe Hatcher actually believed in what he wrote, ignoring anything contradictory to the nonsensical theories he prints in his book.

This is going to torque the sensitivities of those who put Hatcher on a pedestal, and live with a romantic view of Springfield Armory and the Army, but I am going to call Hatcherism the belief that

Cartridges should never be greased or oiled, and the bullets should never be greased. Grease on the cartridge or in the chamber creates excessive and hazardous pressure. It operates to reduce the size of the chamber and thus increases the density of loading and the pressure.

These are Townsend Whelen’s words; General Hatcher did not come up with this belief system , it is in fact based on a data set created by then Major Townsend Whelen, but Hatcher is the “St Paul” of this religion. Without him this would have faded away and at best, would have been a historical curiosity. Hatcher is the source from whom all Hatcherites go, quoting chapter and verses from his 1947 book, Hatcher’s Notebook, on greased bullets, greased cartridges, lubricated cartridges and pressures.

While General Hatcher and Townsend Whelen are educating the public about the evils of greased bullets, they are in fact, only reflecting an Army official position. The Army built over 1 million “low number” Springfield rifles and from Hatcher’s Notebook, about 33% will fail in high pressure incidents. A un known number failed structurally in normal service after firing issue ammunition. The dollar amount for the population of suspect rifles was close to a billion dollars, in today’s money, so this problem is not trivial, nor were the injuries caused. Since the Navy Department, the Marines, and civilians were using this rifle, the cross service embarrassment factor of making and issuing defective rifles would have been extremely high.

No one in the Army accepted responsibility for the defective rifles, in fact, I can’t find the Army ever admitting in public that they made defective rifles. It did leak out after 1927, but I have not found an official statement from the Department of the Army. At the time of the creation of Hatcherism, which goes back as far as WW1, the Army was not telling anyone about structurally deficient M1903’s. Instead the Army is misdirecting the cause of M1903 rifle blow ups onto shooters. The root cause of the Army’s problems with low number M1903’s is the Army’s institutionalized failure to confront problems within their Arsenal system. The human capacity for denial and self deception is infinite, infinite too is the Army’s capacity to shift blame from itself on to others. These behaviors are not unique to the Army; the longer I live, the more I find that all large organizations are totally self centered, have no guilt or shame, never accept fault for the problems they create. And they are all outstanding at finding scapegoats. This is regardless of whether the organization is a commercial concern, a religious organization, or a Governmental unit.

So, what does the historical record say about Hatcherism?:

Well, how could Hatcherism be true, and yet Hatcher be wrong? Here is an excerpt that Hatcher wrote in 1933:

Army Ordnance Magazine, March-April 1933
Automatic Firearms, Mechanical Principles used in the various types, by J. S. Hatcher. Chief Smalls Arms Division Washington DC.

Retarded Blow-back Mechanism………………………..

There is one queer thing, however, that is common to almost all blow-back and retarded blow-back guns, and that is that there is a tendency to rupture the cartridges unless they are lubricated. This is because the moment the explosion occurs the thin front end of the cartridge case swells up from the internal pressure and tightly grips the walls of the chamber. Cartridge cases are made with a strong solid brass head a thick wall near the rear end, but the wall tapers in thickness until the front end is quiet thin so that it will expand under pressure of the explosion and seal the chamber against the escape of gas to the rear. When the gun is fired the thin front section expands as intended and tightly grips the walls of the chamber, while the thick rear portion does not expand enough to produce serious friction. The same pressure that operates to expand the walls of the case laterally, also pushes back with the force of fifty thousand pounds to the square inch on the head of the cartridge, and the whole cartridge being made of elastic brass stretches to the rear and , in effect, give the breech block a sharp blow with starts it backward. The front end of the cartridge being tightly held by the friction against the walls of the chamber, and the rear end being free to move back in this manner under the internal pressure, either one of two things will happen. In the first case, the breech block and the head of the cartridge may continue to move back, tearing the cartridge in two and leaving the front end tightly stuck in the chamber; or, if the breech block is sufficiently retarded so that it does not allow a very violent backward motion, the result may simply be that the breech block moves back a short distance and the jerk of the extractor on the cartridge case stops it, and the gun will not operate.

However this difficultly can be overcome entirely by lubricating the cartridges in some way. In the Schwarzlose machine gun there is a little pump installed in the mechanism which squirts a single drop of oil into the chamber each time the breech block goes back. In the Thompson Auto-rifle there are oil-soaked pads in the magazine which contains the cartridges. In the Pedersen semiautomatic rifle the lubrication is taken care of by coating the cartridges with a light film of wax.

Blish Principle….There is no doubt that this mechanism can be made to operate as described, provided the cartridge are lubricated, …. That this type of mechanism actually opens while there is still considerable pressure in the cartridge case is evident from the fact that the gun does not operate satisfactorily unless the cartridges are lubricated.

Thompson Sub-Machine Gun: … Owing to the low pressure involved in the pistol cartridge, it is not necessary to lubricate the case.


If lubricated cases dangerously increase bolt thrust, as Hatcher says in his Notebook, how come lubricated cases are not dangerously increasing thrust in the blowback or delayed blowback mechanisms? Maybe the laws of physics are different for these firearms than other type of firearms? Maybe one mechanism operates using one set of physical laws and another mechanism has its own unique laws of physics. Maybe certain mechanisms use magic, and operate outside the known laws of the universe. Or perhaps, Hatcherites believe in magic.

What about Melvin Johnson and his comments?:

Army Ordnance Oct 1936 What Price Automatic?, by Melvin M. Johnson, Jr.

Several methods have been devised to retard the unlocking of the block or bolt mechanically. The most appealing point in such a system is consolidation of the “automatic” parts in the breech. However, there is one serious difficulty. The conventional cartridge case does not lend itself to such a system unless adequate lubrication is provided, such as grease or wax or oil on the cases or in the chamber. Thus, the Schwarzlose machine gun has an automatic oil pump: the caliber 30 Thompson rifle (not the caliber 45 T.S.-M.G.) had oil pad in the magazine, and special “wax” was needed on the cases designed to be used in the Pedersen rifle.

Pedersen was granted a patent for coating cartridges with wax lubricants.

PATENT OFFICE JOHN DOUGLAS PEDERSEN, OF SPRINGFIELD, MASSACHUSETTS, Nov. 4, 1930
http://www.google.com/patents/US1780566

In the preparation of cartridges having metal cases for storage and for use, it has been found desirable to apply to said metal case a relatively thin coating of some protective substance which will preserve said metal case for comparatively long periods of time against-deterioration, such as season cracking. In the present invention, the material for said coating has been so chosen as to perform the additional function of acting as a lubricant for the case of the cartridge, both for facilitating introduction into the chamber of the gun and the extraction thereof after firing. The most suitable wax which I have found for this purpose and which I at present prefer is ceresin, a refined product of ozokerite; but I wish it to be understood that other waxes having similar qualities may exist which might serve equally well. Some of the desirable features of ceresin are that it is hard and non-tacky at ordinary temperatures having a melting point somewhere between 140 and 176 Fahrenheit. It is smooth and glassy when hard and does not gather dirt or dust. However, when the ceresin on the cartridges is melted in the chamber of a gun, it becomes a lubricant.

Other lubricating waxes have been employed for coating cartridges, and the method most generally pursued for applying said coating to the cartridge case has been to prepare a heated bath of a solution of the wax in a suitable solvent, dip the cartridges therein so that a film of the solution will adhere thereto, and finally withdraw the cartridges to permit the solvent to evaporate from the coating film. This former process is comparatively slow and has been found lacking in several important respects.


A patent was in 1977 for coating cartridge cases in teflon. It is worth reading the whole patent, I have only copied a small section.


http://www.google.com/patents/US4041868

Polytetrafluoroethylene
US 4041868 A 1977

A thin walled steel cartridge case having a substantially larger internal volume than a conventional cartridge case. The cartridge case is fabricated from a high strength, heat treated carbon steel or boron steel and the wall contour in the head area is designed to avoid localized high stress. A low friction coating is applied to the outer surface of the cartridge case and serves to reduce stress concentrations in the head area and to reduce extraction force in the event of interference between the case and the chamber during extraction


As to the historical use of oilers in fielded weapon systems, I recommend that all read The Machine Gun History, Evolution, and Development of Manual, Automatic, and Airborne Repeating Weapons by George M. Chinn Lieutenant Colonel, USMC VOLUME I OF FIVE VOLUMES

http://ibiblio.org/hyperwar/USN/ref/MG/I/

Do notice that Major General Hatcher is mentioned on the acknowledgements.

Schwarzlose Machine Gun, 8 mm. page 231

This system is appropriately designated retarded blow-back. Due to the fact that the cartridge is extracted under relatively high gas pressure, it was found necessary to lubricate the ammunition. Schwarzlose settled this problem by installing, as an integral part of the weapon, a pump to lubricate the cases. This device pumped a squirt of oil in the chamber between each extraction and loading. The combination of the lubricated ammunition, heavy spring, large bolt assembly, and short barrel allowed the use of an unlocked action which proved quite satisfactory.

Chapter 16 Revelli Machine Gun --251--

An oil pump for automatic lubrication of each round was an integral part of the receiver.

Chapter 8 Nambu Automatic Weapons page 353


All Nambu machine guns were gas operated and air cooled with many radial fins giving more surface for cooling. The earlier models had rectangular gravity oil reservoirs so that as rounds were fed into the feed opening they engaged a spring-loaded lubricator. This action caused oil to flow through perforations onto the cartridge cases. Such lubrication was needed because manufacturing the components to such close tolerances as to permit a workable head space had not been possible at the time. The oil permitted the cartridges to slip back against the bolt until lock clearance was taken up, thereby eliminating the danger of a ruptured cartridge case Such lubrication was needed because manufacturing the components to such close tolerances as to permit a workable head space had not been possible at the time. The oil permitted the cartridges to slip back against the bolt until lock clearance was taken up, thereby eliminating the danger of a ruptured cartridge case


Chapter 9 Revelli Aircraft Machine Gun page 354

The Italian Air Force during World War I was so desperate for an adequate rifle-caliber machine gun of native origin that it ordered the lightening of the water-cooled 1914 model Revelli. This was accomplished by the removal of the water jacket and use of an air-cooled barrel with longitudinal ribs. It not only gave more cooling surface but also strengthened the barrel, cutting down dispersion. The rate of fire was increased by use of ammunition more thoroughly lubricated by means of a built-in oil pump.

Chapter 21 Breda Machine Gun page 416


A large oil reservoir was built into the top of the receiver, directly over the feedway. This lubricator was operated by the recoil and counterrecoil movement of the barrel and barrel extension, squirting oil with each complete cycle on the rounds then being positioned on the floor of the feedway.

Page 419

Like all Italian machine guns oil was used freely on the ammunition since head space was not adjustable on the weapon. The fixed relation between the front face of the breech-lock receiver and the gas port in the barrel made impossible rotation of the barrel in order to advance or retract the chamber for correct head space. The oiling of the ammunition was resorted to in this case in order to compensate for the above condition.


Chapter 29 Sistar Machine Gun page 465

The light machine gun, while having only a 20-shot magazine, did have a feature that the company made great effort to demonstrate on every occasion. The gunner, without rising, could pivot the swinging magazine forward from the prone position and insert in a matter of seconds a fresh supply of loaded rounds directly from the cardboard container into the feed system. By this ease and speed in loading he could keep up practically uninterrupted fire.

The weapon was recoil operated, the barrel having an open jacket that gave it support and a bearing for "floating" the recoiling parts.

A built-in oil pump on the left side of the receiver sprayed a small jet of oil on the incoming rounds as each was positioned for chambering. This device was actuated by the recoil and counter-recoil movement of the barrel extension.


Polsten Cannon page 521

One of the principal differences between the Polish-designed gun, known officially as the Polsten 20-mm Automatic Cannon Mark I, and the original Oerlikon was the built-up receiver of welded construction which had heretofore added greatly to the machining problem in mass production. The Polsten gun was also lighter in weight, but as the weapon was intended for shipboard and ground use, this did not seem of too much importance to the British. It could be fed both by clip or drum magazine, and could only be fired full automatic.


Chinn does not mention that the rounds for the Polsten Cannon were greased but this will be found in Brassey’s “Small Arms” by Allsop and Toomey. In fact, Brasseys Small Arms has a whole section starting page 70 about case lubrication.

The Machine Gun Part V

Chapter 14 Birkigt Type 404 20-mm (Hispano-Suiza) Cannon

--578--
After further comparative tests in late April 1942, it was again definitely decided by the Ordnance Department that all American-made 20-mm automatic guns continue to be made with the chambers longer by one-sixteenth inch than the British regardless of the employment of the same ammunition. This decision was final as far as American production was concerned, but in no way did it change the British representative's view on the longer chamber's performance.

Oddly enough, the question was again raised, not by the English or our many proving grounds, but by manufacturers of 20-mm ammunition. In testing their cartridges for reliability of action, they encountered a series of malfunctions known as light-struck primers that were all out of proportion for such a weapon. These were not isolated cases, the reports coming in from practically every maker of 20-mm ammunition that was engaged in function firing his products.

Since the munitions companies pointed out that the faint strikes were due to lack of impact on the primer resulting from error in the gun, and not as a result of defective materials or workmanship, it was decided to conduct another test on an extensive scale at Aberdeen. Ninety of the 20-mm guns, M1 and AN-M2, selected from every facility producing them, were expended in this test with all types of ammunition, both from accepted and rejected lots.

A complete record was made of every malfunction during the entire test and the probable causes of the trouble. The engineers in charge of the project in the early stages of this test recommended that two modifications should be made to overcome the serious malfunctions:

"(1) Shorten the chamber one-sixteenth inch, thus modifying it to approximately the British chamber.
"(2) Replace the extractor spring with a solid plug, thus positioning the rounds by means of the extractor. This change would include such modifications to the extractor, the bolt, and the ejector, as were deemed necessary."
--588—

During war all that can be done is to install and make function as reliably as possible that which is issued. With the mounting of the 20-mm cannon in Navy, planes a series of malfunctions began that could not be properly corrected at the time because manufacture was at the peak of production. The slightest change would practically mean retooling. The most serious problem was the oversize chamber. There still remained considerable variance in dimensions between the chambers of the British and American cannon, even after the latter chamber was made one thirty-second inch shorter


Due to an outmoded agreement of long standing, everything above caliber .60 in the Army is considered artillery and the manufacture of the Hispano-Suiza cannon therefore came under this classification. In other words the production of this high-speed machine gun was done under artillery manufacturing tolerances. The resulting poor mating of parts, coupled with the inherent fault of all gas-operated weapons whereby the breech locking key in the receiver is immovable and the position of the gas port in the barrel is permanently fixed, made it impossible to adjust the relationship between barrel and breech lock to establish head space. Thus the most vital measurement in any automatic weapon was governed by chance in this instance.

An unfortunate discovery was that chamber errors in the gun could be corrected for the moment by covering the ammunition case with a heavy lubricant. If the chamber was oversize, it served as a fluid fit to make up the deficiency and, if unsafe head space existed that would result in case rupture if ammunition was fired dry, then the lubricant allowed the cartridge case to slip back at the start of pressure build up, to take up the slack between the breech lock and the breech lock key. Had this method of "quick fix" not been possible, the Navy would have long ago recognized the seriousness of the situation. In fact, this inexcusable method of correction was in use so long that it was becoming accepted as a satisfactory solution of a necessary nuisance.


Over 150,000 of these machine guns were built by General Hatcher's Ordnance Department during WW2, and they all used greased rounds. The Navy also used the same mechanism. There is a neat copy of the manual for the Oerlikon at the web page referenced below

20 mm Oerlikon



http://archive.hnsa.org/doc/gun20mm/index.htm


quote:
GREASING AMMUNITION

All 20 mm. A.A. Mark 2 and Mark 4 ammunition MUST BE COMPLETELY COVERED WITH A LIGHT COAT OF MINERAL GREASE BEFORE BEING LOADED INTO THE MAGAZINE.

The ammunition is usually packed greased. However, this grease tends to dry off. Whether cartridges are packed greased or not, they should be regreased before loading the magazine.


NOTE-A small amount of mineral grease, applied shortly before firing, to the cartridge case that is visible in the magazine mouthpiece, will assist in preventing a jam in the gun barrel.

Dry ammunition or ammunition with insufficient grease will jam in the gun chamber when fired and extraction will be very difficult, if not impossible. See Page 110 for use of torn cartridge extractor.



NOTE-Oil must not be used as a substitute for mineral grease.

Sufficient grease should be present on all cartridge cases to be easily felt by the fingers. An excess should be avoided.

CAUTION-Do not grease the rear end of the cartridge cases as the grease has a tendency to percolate inward past the percussion cap. NEVER USE OIL.


So, as a sort of wrap up, warnings about increased chamber pressures, increased bolt thrust, how credible are those based on the historical use of grease, oils, waxes, and Teflon? And, considering all the weapons systems that used grease, oils, and waxed cartridges that Hatcher shot, built, fielded, as head of the Ordnance Department, how could he write what he did in Hatcher's Notebook? Is Hatcherism based on science, or magic?


Virtually every time I mention my use of lubricated cartridges, or I recommend lubricating cartridges, I get a knee jerk "Oh my God!" reaction. Then I am constantly reminded that lubricated cartridges were used in the British proof test, with the assumption that lubricating cartridges has to be dangerous because the purpose of proof is to blow up the mechanism. The second part of the sentence is the story that people create in their minds, and after, I believe, reading Hatcher's Notebook. Hatcher mentions that the early single heat treat 03's were blowing up in the field, so Springfield Armory increased the proof pressures, to blow up more 03's before they got out the door. Somehow people contort this section into a belief that the purpose of proof was to blow up rifles and that lubricating cartridges helps that process. Nothing is further from the truth. Unless the cartridge is lubricated the locking mechanism is not fully loaded, due to parasitic friction between the case body and the chamber. Therefore any proof tests with dry cartridges and dry chambers is technically unjustifiable as the locking mechanism is not as uniformly loaded as the chamber. This is recognized in NATO EPVAT testing. https://en.wikipedia.org/wiki/NATO_EPVAT_testing NATO EPVAT testing specifically calls out the testing of firearms with an oiled proof load as the final test.

Something that people miss in Hatcher's account of the Army's actions is that Springfield Armory did not attempt to figure out why their rifles were blowing up in the field, why these rifles were structurally deficient, and they did not look at fixing the problem within the factory. Instead of examining their processes and finding the source, the Army implemented the lazy man's approach: they raised proof pressures at the end of the production line and blew up more rifles. Implicit, but unstated in their actions, is that the Army accepted that a certain percentage of defective rifles would be created on the production line, would pass a higher pressure proof, and would be shipped to the troops. Structurally deficient rifles did pass the more stressful proof test only to fail later, in the field.



* There are people who believe that the case is a load carrying member. They did not come up with this idea on their own, this was something they were taught. It all came about from the early 1900’s problems with the single heat treat 03 Springfields and the Army coverup of these problems. The 03 Springfield was properly designed to carry the full thrust of the cartridge case, but the single heat treat Springfields were not properly built. The Army built over 1 million structurally deficient rifles, kept them in service, issued them, sold them to Civilians, and whenever rifles blew up, blamed the blowups on the shooters. To give logic to this cover up, the Army created this theory that the case carries load and removes load from the bolt face. There was actually a method to this madness as at the time shooters were greasing their bullets, because the bullets of the period fouled something awful. Grease eliminated the fouling. Instead of acknowledging that their defective rifles were at fault, the Army told people that grease in the chamber removed the friction between case and chamber (which is true) and thus, dangerously, increased bolt thrust, which is the lie,... sort of. In a properly designed rifle firing ammunition within specs, there is no problem whatsoever with greased or oiled cases, but in a defectively designed or defectively built rifle, ANY BOLT THRUST is a problem. The Army successfully scapegoated innocent shooters and misdirected the problem they created. The authority of the US Ordnance Department is so high that no one has ever questioned this, nor challenged the idea that anyone would so stupidly design a rifle to break at a load less than the full thrust of the cartridge. Instead, you have generations of people faithfully adhering to the lie that the case is supposed to carry load, and there will be generations more will believe this in the future, such is shooting community’s belief in the infallibility and inerrancy of the US Army Ordnance Department. In fact, even today, whenever any problem happens with an Army weapon, the first thing the Army looks for is an oil can to blame.
 
Posts: 1195 | Registered: 10 October 2005Reply With Quote
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Thanks for putting that up Slamfire. I found that very interesting.
In the New Year, I'm going to be playing with some different powders and once I work out some safe maximums, I'll drop some charges down and lightly grease some rounds and see if I get any discernible effects.

Kevin
 
Posts: 15 | Location: Australia | Registered: 07 October 2015Reply With Quote
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From theSierra manual.



From the Lyman manual.



From the U.S. Army.



Below from the 1929 British "Textbook of Small Arms. The British used the base crusher system where the copper crusher was located at the base of the case. The base crusher system measures the chamber pressure "AND" the actual amount of bolt thrust. Bottom line any oil, grease or water in the chamber increases bolt thrust. And in a dry chamber the case gripping the chamber walls and the case stretching to meet the bolt face reduces bolt thrust.



Below from the Springfield Armory manual for the M1A.

Do not oil cartridges, and be sure to wipe the chamber clean of any oil or preservative before commencing to shoot. Oil actually
interferes with the friction between cartridge case and chamber wall that is necessary for safe functioning, and subjects the
firearm to stress similar to that imposed by excessive pressure.

http://www.springfield-armory....014/03/M1AManual.pdf
 
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Parker Ackley was a well known gunsmith located in Salt Lake City in the late 50's and into the 60's. He wrote several books, one of which was "Volume One: Handbook for Shooters & Reloaders". His specialty was the development of wildcat rifle calibers which he created and tested and built rifles for. He was also a contributing gunsmithing editor for "Guns and Ammo Magazine" for a number of years. In the handbook I mentioned above in a chapter entitled "Pressure" (page 138 and following), he talks about an experiment he did with an old Model 94 Winchester. Briefly, he removed the locking lugs from the action. Then he rechambered the barrel for his 30-30 Improved (less taper to casing walls than a standard 30-30). With the lugs removed from the action, he fired two standard factory .30-30 cartridges. Prior to shooting, he made sure that the chamber was clean and dry. The rounds he fired formed to the Improved chamber perfectly with no primer back out. Then he unscrewed the barrel one turn and fired two more rounds. The primers backed out equal to one barrel thread, but the cases did not back up against the bolt, which means that the brass case withstood the pressure. Two more factory cartridges were lightly oiled. The primers did not back out, but the shoulders of both rounds were blown forward the distance of one barrel thread. Thus the oiled cases did not adhere to the chamber walls but backed up against the bolt face. Last, he unscrewed the barrel two full turns and cleaned and dried the chamber. He fired two more factory rounds. The 1st casing remained tight in the chamber but the primer fell out. (He lengthened the firing pin to fire the rifle). He then oiled the case of the second round and fired it. The casing stretched and separated just above the base, indicating that it again did not grip the chamber walls and expanded back to the bolt face until it separated. He felt that this experiment proved that a clean, dry chamber will allow a cartridge case to grip the walls of the chamber and not move back against the bolt face in most cases, making the actual back-thrust pressure on the bolt face itself little or none.
 
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quote:
Originally posted by SlamFire:

I really tried to make it clear, lubricated cases do not relieve chamber pressure, at least not significantly. Grease or oil might slightly reduce chamber pressures, and this is tentative, because oil or grease on the case will be squeezed up into the chamber throat, reducing friction between bullet and barrel. This has not been tested enough to really prove that point. This chart comes from an Army cover-up, I don’t want to get into that cover-up right now, but this data was useful. They fired heavily oiled cases and it did not increase chamber pressures.



f


Makes me wonder who is trying to cover up information on lubing cases. And makes me wonder "WHY" the last page of the test was not posted by SlamFire.




The title to the link below says it all

Lubrication’s Contribution to Cartridge Case Failure

http://www.dtic.mil/ndia/2011ballistics/11826.pdf

Good job SlamFire of trying to mislead forum members about Military warnings, firearms manufactures warnings and reloading warning about lubing cases.

OK people its safe to believe faceless strangers on the internet..............

So smoke 'em if you got 'em (it won't hurt anything)

SURGEON GENERAL'S WARNING: Smoking Causes Lung Cancer, Heart Disease, Emphysema, And May Complicate Pregnancy.
 
Posts: 217 | Registered: 29 July 2009Reply With Quote
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eagle27 hit the nail on the head. Now that you have fired cases (with mild recoil / pressure), I would try to increase load back towards 47 gr to reach most accurate load that is safe and gives you optimal velocity.

DO NOT lube cases. That is done with starting loads for fire forming wildcat calibers to ensure smoother flow of brass.


"When the wind stops....start rowing. When the wind starts, get the sail up quick."
 
Posts: 11006 | Location: New Zealand | Registered: 02 July 2008Reply With Quote
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Your head clearance is the distance from the rear of the case to the bolt face. The head clearance is equal to how far the shoulder was pushed back during sizing.



When the cartridge is fired the primer is pushed out of the primer pocket and then the case stretches to meet the bolt face.



The higher the chamber pressure and the more head clearance you have the more the primer will flatten and mushroom when fired. This is why for longer case life you see it recommended that you only bump the shoulder back .001 to .002 for a bolt action rifle. This .001 to .002 amount of head clearance does not exceed the brass cartridge case elastic limits in the base and the case does not stretch and thin in the base.



Simple Trick for Monitoring Pressure of Your Rifle Reloads.

http://www.hodgdonreloading.co...e-your-rifle-reloads
 
Posts: 217 | Registered: 29 July 2009Reply With Quote
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Below a fired case from my AR15 carbine.



Below the same case after full length resizing and .003 shoulder bump.



In over 47 years of reloading I have never had a case head separation. And I "NEVER" lube my cases, and with proper resizing methods lubing your cases is never needed.

The illustration below tells it all, you only need to push the shoulder back .001 or .002 below the red dotted line. And the further you push the case shoulder back toward the green dotted line the more the primer can back out of the primer pocket. And also the more the case can stretch past its elastic limits which leads to case head separations.



The above messages were brought to you by the "NON" case greasers of America. We are smart, very good looking and exceedingly modest. tu2
 
Posts: 217 | Registered: 29 July 2009Reply With Quote
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quote:
Originally posted by bigrdp51:
quote:
Originally posted by SlamFire:

I really tried to make it clear, lubricated cases do not relieve chamber pressure, at least not significantly. Grease or oil might slightly reduce chamber pressures, and this is tentative, because oil or grease on the case will be squeezed up into the chamber throat, reducing friction between bullet and barrel. This has not been tested enough to really prove that point. This chart comes from an Army cover-up, I don’t want to get into that cover-up right now, but this data was useful. They fired heavily oiled cases and it did not increase chamber pressures.



f


Makes me wonder who is trying to cover up information on lubing cases. And makes me wonder "WHY" the last page of the test was not posted by SlamFire.




The title to the link below says it all

Lubrication’s Contribution to Cartridge Case Failure

http://www.dtic.mil/ndia/2011ballistics/11826.pdf

Good job SlamFire of trying to mislead forum members about Military warnings, firearms manufactures warnings and reloading warning about lubing cases.
]


Well Eddy Horton did a good job of finding the Army cover-up that I did not want to get into. Just like Eddy, it is a distraction. But it is worth looking at.

I don’t want to be too harsh on Eddy for failing reading comprehension, for the first time I read the study, I did not pick up on what they were doing. I had to read it a couple of times to figure it out. But, the study can be summarized in one sentence: the Army fired over pressure ammunition and blamed oil for the malfunctions they encountered. What was particularly upsetting was the incredible incompetence of the Army Ordnance Corp as shown by their actions and their omissions. For example, it is apparent that the Army Ordnance Corp did not know that cooking the ammunition at 160 °F raises combustion pressures. And then, firing the ammunition in a 160 °F full auto weapon, it is also apparent that they did not know that weapons have thermal limits, and over heating a weapon will cause malfunctions. If you have half a brain you can see that their predicted pressures are extraordinarily high, and it is a testament of good design that the SAWS did not come unglued with such over pressure ammunition.

The study was useful in that they have data showing that oiled cartridges don’t raise combustion pressures, and that is about it. The weak and feeble minded won’t notice the details, or notice the omissions, instead, will be mislead by large print banners.

One omission, which was very startling, it is apparent the Army Ordnance Corp does not know their firearm history. Even though the Federal Service attracts low motivation, low intelligence, high personality issue types, you would expect that they would at least know the history of firearms and address why their machine gun would not work with lubricated cases, when billions and billions of rounds were fired in fielded systems. Eddy has completely ignored the list of fielded weapon weapons that used oiled or greased cartridges, and this is something he needs to address. Eddy needs to prove that he can do more than simply copy and paste from other people’s work, and reconcile the difference between the historical record, and all the scientology that he posts as proof.
 
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SlamFire, instead of blaming the military, the firearms manufactures and the reloading industry for a cover up. And claiming you are the only person in the world who is a expert about lubing cases I have a great suggestion.

Read up on the base crusher system and how the British measured chamber pressure. That way you will learn something about bolt thrust and "WHY" you are told to "NOT" lube your cases and to remove all oil and grease from the chamber and bore before using your firearms.

Then read up on P.O. Ackley, his case designs and how they reduced bolt thrust.

I could go on, but after over eight years of trying to get you to see the light on not lubing your cases I know its a hopeless cause.

Cartridge Pressure Standards
http://kwk.us/pressures.html

Measuring Cartridge Pressures

In Britain, a third set of crusher standards were developed, using a "base" crusher. The crusher was a short, thick tube placed behind a piston at the base of the cartridge, and the firing pin passed through the center. The cartridge case was well oiled before firing, to minimize cling to the chamber walls (if not oiled, the indicated pressures were about 25% lower). To prevent case rupture on set back of the base, the crusher was first deformed in a press to a pressure a bit lower than that expected in firing. The units were generally stated in British long tons per square inch, or tsi.

From the 1929 British Textbook of Small Arms



And last but not least from the H.P. White Testing Laboratories.



When it comes to firearms history and bolt thrust "YOU" are the one lacking in basic knowledge of what causes bolt thrust.
 
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Wow, way too much drama here. For all you new reloaders and shooters; please do not lube your ammunition in any way before firing, regardless of what you might read here. It is a bad idea.
 
Posts: 17046 | Location: USA | Registered: 02 August 2009Reply With Quote
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Just imagine someone who lubes his cases and thinks he knows more than the engineers at Aberdeen Proving Grounds. And they tell you to not lube your ammunition. And this command has all the test equipment to prove and backup their statement. And SlamFire thinks its a military cover up conspiracy.
bsflag


RDECOM - U.S. Army Research, Development and Engineering Command

Department of the Army
U.S. Army Research, Development and Engineering Command
3200 Raritan Ave.
Aberdeen Proving Ground, MD 21005



A Army wide conspiracy, in all their commands......yeah right. dancing

 
Posts: 217 | Registered: 29 July 2009Reply With Quote
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quote:
Originally posted by bartsche:
oldIn tail gunner's photo:
the middle primer gives the appearance of reasonable pressure and possibly too much head space.

The primer on the right has a severe mushroom , darkened metal and shortened primer height indicating high temperature and presure, and meaningful metal flow.


Bartsche etal
The rifle that fired the left and middle cases (30-06) has a headspace of -.002 (that is to say it almost closes on a GO gauge). Load is 61.5gr of Re-19 and a 150gr NBT. Sizing is PFL to 2/3 of the case neck.
The over load was from a 300 RUM Improved case, and was IIRC 10gr over book max for the RUM case (load was a computer calculated "starting" load) OOPS.
 
Posts: 2124 | Location: Whittemore, MI, USA | Registered: 07 March 2002Reply With Quote
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quote:
Originally posted by bigrdp51:
Just imagine someone who lubes his cases and thinks he knows more than the engineers at Aberdeen Proving Grounds. And they tell you to not lube your ammunition. And this command has all the test equipment to prove and backup their statement. And SlamFire thinks its a military cover up conspiracy.

bsflag


RDECOM - U.S. Army Research, Development and Engineering Command

Department of the Army
U.S. Army Research, Development and Engineering Command
3200 Raritan Ave.
Aberdeen Proving Ground, MD 21005



A Army wide conspiracy, in all their commands......yeah right. dancing


Looks like you need to do some research yourself before flaming others.
Please explain to me why NATO uses greased cartridges on all of their pressure and bolt thrust tests.
NATO are the ONLY ammunition testing org in the world still using greased rounds for bolt thrust comparison, they don't say that greased rounds INCREASE PRESSURE, ONLY BACK THRUST ON THE BOLT FACE.
I believe slamfire is correct, greased, lubed or oiled cases DO NOT INCREASE pressure. A lubed, greased or oiled BORE does, as I have tested this fact on my Pressure Trace. I am yet to test greased cases/chambers, but hope to do so early next year when I'm less busy.

wave
 
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