pshooter...wow that was telling us but in reviewing my posts I don't think I took but a very small "shot" at you...most of what I posted was in support of riccardelli. I certainly am not the "king" of reloading; I have been doing it for quite awhile but there are lots and lots of shooters who both a larger variety of experience over a longer time BUT I do read some of the better journals and I do have a lot of friends who could be considered experts so I learn a little here and there.

I also hunt, not as much as I would like, but I get around a bit (nothing like a career in the USAF and having Uncle Sam send you to exotic places) and have managed to hunt in Asia, Europe, Africa (two safaris) and of course the US including living and hunting in Alaska for 4 years.....probably not nearly as exciting as shooting 4 or 5 100-pound white-tails from tree stands each year but it's been fun for me.

I believe and appreciate the fact that you would throw me out of your business...not to worry as I rarely stop at road-side stands even if the peanuts and pork-rinds for sale are cheap. Thanks anyway.

By the way...if your next snappy comeback is about the relative size of our dicks I'll conceed you're the bigger dick.

[ 07-28-2002, 10:35: Message edited by: DB Bill ]

psshooter-
You have been given some good info from The Nice Folks.
I do Measure around the case head Dia-Cailpers as well as watch primers,sticy bolt, and vel.readings.When working with a new gun I try to find a Factory Load of the same bullet as I will be using or at least the same weight and in the same brass as I will be using.I leave 5 as is,pull 5 and seat my Bullet on the factory charge.The rest are pulled and recharged with my chosen powder and bullets,I may also re seat the factory bullet over my own powder charges.After shooting each one and watching for any signs of pressure.I start measureing at the neck,then slide the case though the Cailpers to the case head,make a note of the widest measurement,then 1/4 turn the case and redo untill all the way around.Doing this on all the cases.When I find one that is out specs with the Factory loads I consider that laod to be Too Hot for the Gun fired in.An examaple of this would be the .300 WSM I'am working with now,using 150 gr Nosler partitions and different Powders.
All case's have come out the same so far .554 to .555 in fornt of the case head,no other signs of pressure have been seen yet.I have found one load thats measures out at .556 I will reduce this load 1 full grain if I where to use it.
I saw this in one for the many Reloading Manuals I have.May be alot of work but it works for me.

DB Bill, I have to say you made me laugh. While your perception of me is not completely accurate there are those here (ga) that it would apply to.
To me the stupid questions are the ones not asked. And I don't hunt from stands..I like to get in amongst what I shoot. Good luck in your career, I'm shure your boss thinks your the greatest. mvm

Sysephus, you will NEVER be able to use case expansion, regardless of which hinder-part of a case you care to measure, as a RELIABLE INDICATOR of safe vs excessive pressure levels. One of the last two Lyman manuals has a series of pressure readings taken from some .30/'06 ammo in a pressure gun, and the micrometer readings from each case. In a couple of these shots, the case expansion was LESS and the pressure MORE than others shots which had MORE EXPANSION!! It just isn't reliable. But, "case life with repeated reloadings" at least tells you which loads are most "reasonable" for a reloader who is trying to optimize the use of his components, and not just seeking MAXIMUM VELOCITY readings!! Just because some old "expert" like Ken Waters, bless his old soul, has used the method since the Good Lord was a Road Guard doesn't mean he has been getting useful information!! He never loads for maximum velocities anyway (which is a good thing, of course).

[QUOTE]Originally posted by ricciardelli:
[QB]A quick question back to you...does the "bulge" go totally around the case, or is it just in one area?

Thank you for the reply.

The "bulge" is a ring and not a bubble. I am using a Dillon Square Deal B press, and the sizing die is all the way down. You can sometimes see the bulge without benefit of a caliper, at other times, cases I would swear would not fit the guage go in nicely.

From what you said, it probably is the Glock causing the problems. I wish I had known about it before I contaminated my other brass. I wouldn't have had to resize the whole lot and run them through the guage before I reloaded them.
Thanks again for the reply

PSHOOTER

THANKS FOR ASKING THE QUESTION OF "PRESSURE." I KNEW WHAT YOU WERE ASKING...YOU WANTED MORE INFO THAN YOU HAD READ IN THE MANUALS. FUNNY HOW SOME JUST ARE WAITING TO "UNLOAD" IN THE "RELOADING" FORUM. I LEARNED WHAT I HAVE SUSPECTED THAT UNLESS YOU HAVE THE EQIPMENT THERE IS NO RELIABLE SOURCE EXCEPT STARTING LOW AND WORKING UP FROM SEVERAL MANUALS PUBLISHED LOADS. HAPPY SHOOTING.
YOU ARE RIGHT "A DUMB QUESTION IS ONE NOT ASKED."

Someone stated back there a ways, that case head expansion, measured at the un-supported area, was not affected by chamber size. To my way of thinking 'taint so. I'm having difficulty expressing in words how I see it. But basically, the unsupported portion of the case must angle outwards to meet the chamber. So even if you use a knife edge micrometer, it's going to be difficult to determine what area of the case is uneffected.
I'm not saying that it's not usefull, it is!, but On a large chambered gun, it MAY not be accurate on the first reload. The second reload of the same case should be a better indicator.

PSHOOTER,
Perhaps I erred in my interpretation of you original post. I thought I had answered your question to the best of my ability. If I failed to do so, I'm sorry.

Granted, there are some people have a bad day and perhaps get a little carried away. I don't however think that your response was anything I care to be subjected to in the future. In my career either in the marine corps and as a police office I think I've heard it all. The best/worst one was a "lady" who had mirrors on her ceiling and who I'd just placed PD jewelry on. That was all part of the game. You, I don't have to suffer. I've gotten old enough where wasting time is not a good idea. I for one will not bother you again.

pshooter,
Wow, I just opened this and didn't see anything you said to get the monsters riled up. It seems if you ask for help, two kinds of people will emerge. Those who wanted to help gave you some good advice. The others that just want to feed their ego are best left to their playpen or better left to feed on those that are willing to play their childish games. I have found this place to have some good genuine folk who are willing to help. The sorting process is often very easy to do.

I have been loading some time over 5 years but your post sounded interesting and I did enjoy those responses that addressed your question.

Hot Core wrote:

First off let me say I'm not a fan of the Strain Gauge devices for knowing when your Handloads are SAFE. That is because; 1. The inherent variances involved with attaching them to a chamber. 2. I REALLY dislike the idea of having a Strain Gauge attached to the barrel of one of "my" firearms. 3. The Calibration of the entire system is done with an "Unknown" which means any decisions made concerning a Load are just guesses. 4. The actual(unknown-calibrated) Pressure information is Second Hand since it does not come directly from the actual case. 5. And the cost of the things are a bit stiff for many folks.

Hot Core--
I hesitate to post after some of the responses on this thread, but I've been doing some work with strain gauges, and have a couple of comments that might interest you. So, in hopes that it is interesting/useful:

There really isn't much of a trick to getting strain gauges properly mounted. Just clean the surface with solvent, slap a thin coat of epoxy on the gauge and the barrel, put the gauge in place, then hold it down with electrical tape, pulled very taut over the top. I put mine on the botton side of the barrel, just ahead of the receiver, where they are completely out of sight. However, as you point out, it's not for your collector grade pieces.

It really isn't as expensive as some folks think. Strain gauges are about $10-15 per firearm, and the meter is about another $150, at www.fabriquescientific.com.

Actually, strain is probably the most fundamental measurement you can make to estimate maximum safe load. All the materials and dimensions are chosen so as to not impose too much stress on the steel, and strain is directly proportional to stress in the safe operating region. PSI is actually a less fundamental way to predict the failure point of the metal.

Calibration is an issue, as you quite correctly point out. Lacking access to the special calibration ammunition that commercial establishments use, the next best thing is to calibrate from the dimensions of the chamber, which you can get to within .001", and the physical properties of steel. That actually gets you quite close. So it's not really tooooo bad. Also, you may not have a perfect absolute calibration, but the relative values the system produces are very repeatable, and that is useful.

You guys have been sniffing you powder cans. Ease up. It is just as easy and safe to load to pressures that don't stress your components. Who cares about 100 feet per second?

Hey denton, Thanks for the reply. I understand what you are saying about the Strain Gauges. It sounds like they are much better than the ones I used for many years. Ours were very fragile. Anyway, I'm glad to hear they are better than they used to be.

Your post brought out one other thing I'd neglected to mention - getting an accurate measurement of the chamber thickness where the Strain Gauge will be attached. I forgot to mention it in my original post, realized it a day or so later, but thought the thread had died off and didn't bother to "edit" it in.

When I used Strain Gauges, I had access to CMMs that would allow very precise measurements "IF" you could get the "Touch Ball" into the spot you were trying to measure. We had some on fairly long arms(which degrades the accuracy slightly), but they worked fairly well.

I'd appreciate it if you would describe the current method you use to determine the chamber thickness. I realize if you mention using a 0.0001" capable Micrometer that it will open you to ridicule from people who think they are totally worthless. And if you mention measuring the outside of a fired case with them to get the "inside" chamber dimension, then you will be basically be VALIDATING the use of the same Micrometers to measure CHE and PRE.

Seems to me there would have to be a "Fudge Factor" thrown in to allow for the case shrinkage after firing, and of course that would "also" degrade the accuracy of the Strain Gauge measurements.

Or, are you using Plug Gauges? Of course, to hear some folks tell it, ALL chambers are out of round so bad it is a wonder a case can be chambered. And of course that would invalidate the Plug Gauges having any "super-duper accuracy"!

If outlining this portion of the Set-Up makes you feel uncomfortable about posting it, I will understand. Quite a few folks got fooled into thinking the Strain Gauge method is "Perfect", when in fact, it has it's own unique set of issues that keep it from being totally accurate.

That is why I recommend people "use EVERY Pressure Detection Method" they have access to, they all have their own unique quirks.

You are only the "third" person I've seen acknowledge the inherent set-up problems with the Strain Gauge devices. Thanks again for the great post.

[ 08-03-2002, 20:28: Message edited by: Hot Core ]

Thanks for all the input guys. BigBob, You answered me with information not ass thus all my abrasive comments were not directed at you or other courteous posters. I, as well as others value the info on this board so thanks. As far as the police jewelry, it can be used in many "special" ways!(hehe)mvm

Hot Core---

Well, I had to think for a few minutes about how to get the ID of the chamber, for all the reasons you mention.

My solution was a narrow strip of .005" shim stock, Krazy Glued to the outside of the case. I inserted the case until it stuck fairly firmly. Then I put a dowel down the muzzle, to the bottom of the empty casing, and marked the dowel where the muzzle was. I then removed the casing, picked the spot on it where I wanted the strain gauge, and laid the dowel and casing on top of the barrel. I then measured the OD of the barrel and the OD of the casing plus shim at that point, using a McDonalds Happy Meal ruler....er... ordinary dial calipers. Getting the dimensions within .001" or so is adequate. I repeated the measurement a few times and took the average, just to be sure.

I had this absolutely grand idea for using several loads which had published PSI figures, and doing some fun stats to validate my calibration. That one failed gloriously. The batch to batch variation of powder is far too great to let that work, even after you hold your nose and ignore chamber to chamber differences.

One suggested approach is to buy several types of commercial ammo, and simply use commercial ammo pressures as an upper limit. I haven't tried that. For one thing, I'm embarassed to buy assembled ammo.

The good news is that I have run some stats on the consistency (neatly ignoring the problems discussed), and you can produce strain gauge pressure numbers at home that are as consistent as published CUP and PSI data.

Hot Core...

The problem with measuring the head expansion at the base of the cartridge is that the case heads have a "range" of hardness that is acceptable, and in a given lot of cases, with the same charge, each case will expand to a different degree, so it becomes meaningless... the case head expansion thing became popular in the early 70's, and was the absolute rage.
It sounded so scientific. But it died out a few years later, and now has no scientific value... wanna buy a hardly used Starret blade micrometer??

But to the strain gauge thing... there is a company that now makes a clamp on strain guage that attaches to the gun without epoxy, and is technically an "Accelerometer"... just know the weight of the gun, and the weight of the other components, bore size, etc, and knowing the acceleration, it computes the chamber pressure... much better than the pastie method, as there are no errors from differeces in metal hardness, (or not knowing the metal type at all).

You can also run the leads parallel to a high impedance storage ocilloscope, and read the whole trace for the entire pressure curve.

It goes on and off in minutes with no damage to the guns finish, and they are under $500.

CatShooter.

[ 08-04-2002, 05:13: Message edited by: CatShooter ]

ElViejo,
I had a problem similar to your many years ago. I had a definite bulge just ahead of the extraction grove on one side of my spent brass. I concluded that this was the result of the weapon beginning to extract too soon. I returned the pistol to Taurus with several of the spent cases. They returned the pistol with a new barrel, and the problem stopped. Ku-dude

Ku-dude,
Thanks for the post.

Eldeguello...just a quick count in the two volumnes of "Pet Loads" by Ken Waters...Umm...seems there are 97 or so different CARTRIDGES reloaded, with any where from 50 to well over 100 separate LOADS given for each cartridge....nowhere did I find any duplicates. Seems to me he might have gleaned just a touch of useful information in 7000 or so worked up loads. All of which were measured for casehead expansion, (according to Ken). And he learned his pressure signs reading from such old experts as Ned Roberts, Colonel Whelen, Jack O'Connor, Warren Page, and some young experts such as Neal Knox, (his boss on Handloader), Mike Walker, from Remington, Bob Forker, Homer Powley, and on, and on, and back in those days, you relied on your micrometer, (not a digital in the bunch, either),to keep all your eyes in your head, and all your fingers intact....You know, Ken Waters wasn't always old, for quite a while he was a rather young expert. And make no mistake about it, he was an expert.....Perhaps the most expert reloader of all time. And speaking of loading for maximum velocity, lots of Ken's loads are considerably hotter (and faster) than lots of the "maximum" loads given in the current lawyer-shy reloading manuals......I guess my advice to Ps Shooter, would be to ask questions, feel your rifle, read that brass, check that chronograph, and for sure, use that mic........

Hey Denton, Sounds like as good a way as any to do the "estimate" of the Chamber Wall. None of the other folks that talked about their Strain Gauge devices have been as open about having to "estimate" and "guess" at portions of the Set-Up Procedure.

Seems to me you have a much better grasp on the "validity" and "value" of the resulting measurements than the other folks I see mention using them. I do realize they provide somewhat good information, but as you, I realize they have their own group of limitations.

quote:

---

Originally posted by CatShooter:
Hot Core...

The problem with measuring the head expansion at the base of the cartridge is that the case heads have a "range" of hardness that is acceptable, and in a given lot of cases, with the same charge, each case will expand to a different degree, so it becomes meaningless... the case head expansion thing became popular in the early 70's, and was the absolute rage.
It sounded so scientific. But it died out a few years later, and now has no scientific value...

But to the strain gauge thing... there is a company that now makes a clamp on ..."Accelerometer"... just know the weight of the gun, and the weight of the other components, bore size, etc, and knowing the acceleration, it computes the chamber pressure... much better than the pastie method, as there are no errors from differeces in metal hardness, (or not knowing the metal type at all).

You can also run the leads parallel to a high impedance storage ocilloscope, and read the whole trace for the entire pressure curve.

It goes on and off in minutes with no damage to the guns finish, and they are under $500.

CatShooter.

---

Hey CatShooter, It sounds like you had a problem reading the Micrometer or believing what it told you. If you were using a 0.001" capable Caliper instead of a 0.0001" capable Micrometer, that could be part of your problem. However, even with the very best Micrometers, Loads and l-o-t-s of experience, there is still some "varience" in CHE & PRE measurements. Those come from the differences induced during manufacturing of the raw Case material and the actual manufacturing of the Cases.

The "problem" of the variance with CaseHeadExpansion is the portion that is of the utmost importance to me. As I feel sure you know, the Case is the Weak Link in the entire firing process. Being able to see this "variation" tells a person when to STOP adding Powder with more confidence than any other method I've tried. Watching the Primer Pocket Expansion, Primer Condition, Bolt Lift, and Primer Pocket Shortening seem to be the only other Pressure Detection Methods which actually include the Case as the "Weak Link".

As far as "scientific", it seems to be more scientific "to me" than having to "estimate and guess" at the results of the device. Plus it is First Hand information, not Second Hand info like the Strain Gauges provide.

One of my buddies had mentioned seeing something about an Accelerometer device to measure Velocity. Kind of caught me off guard. I've also used One Shot Accelerometers when measuring the Impact of Packaged Materials being dropped from various heights. And they worked well in a "Free Fall" situation.

If you can answer these questions, I'd be grateful. How does this new device compensate for a guy my XXXLARGE size holding the rifle tight against his shoulder, and then handing the same rifle to a little whimpy Small size shooter holding the same rifle loose in his shoulder?

Does the rifle have to be fired while it is hung in the air by a couple of ropes?

Do they make calibration changes depending on the type of recoil pad?

How is the device calibrated?

I'm not challenging your input. I just don't understand how the method could be accurate when a "held firearm" has different amounts of resistance-to-recoil from different shooters.

Hey Oldmodel70, UUUuuuhhhh, VERY Well said!

Best of luck to all you guys with your Reloading and use every Pressure Detection Method at your disposal.