Customer has dropped off several of his Mauser "projects". One of them is a 98 Brazilian action to have a prefit installed- a McGowen that he's had in .300 Win Mag, together with CDI (DBM) bottom metal to be fitted in a PH Target stock.

Kuhnhausen recommends against using 98 actions for magnum length cartridges due to the significant amount of steel that needs to be removed from the feed ramp. If I were to go with max available with the bottom metal, I'd be milling out roughly the lower/steeper section of the feed ramp completely.

I'm sure thousands of 98 Mausers have been altered to accommodate the big magnums, including safari rifles in .375 H&H, .416 Rigby and others.
This receiver has some minor surface pitting, but lug abutments aren't set back/passes visual inspection.

Bolt is not original. If it's not chrome plated it's the best/brightest polishing job I've ever seen , fitted with a Buehler safety. Quick Dykem check shows only top lug contact, so I'll need to lap the top until I get adequate bottom contact.
Boltface has already been opened up for the Win Mag, but the rim on the go gage won't clear the extractor (I'll need to pull it and grind clearance) so it apparently hasn't been used.

Compared to many here I've got limited experience with the Mauser- are the big bore safari magnums unsafe conversions?

Isn't the 300 win the same length as an 06 ?

quote:

Originally posted by robert lerner:
Isn't the 300 win the same length as an 06 ?

No.

^^^
SAAMI spec, yeah...
But who loads to SAAMI OAL these days, with heavy VLDs?

SAAMI is 3.34 for both, but it's not uncommon to have OALs in the 3.7-3.8 range with heavy VLD's

I've emailed the customer asking what bullet weight/type he might use, AICS mags for the .300 WM are available to accommodate up to 3.85

Pending an answer from the customer, I wanted to see what the wisdom is on this. I've got 3.46 in the magwell now, I'd like to give as much as can be done safely

there is only going to be a couple grams removed to make a 300 win feed in a mauser, its a 3.35 oal cart, not a 3.65

*MY* problem, assuming its a 1908, is that the action may be soft

Length ain't the problem; back thrust is. And particularly on the pre WW1s like your 08, it was made at DWM. Mauser was busy with Turkey at the time. What is not recommended is the H&H length due to the fact that most guys remove all the metal from the lower locking lug abutment; although that has been done many times too. But not germane here. I remove metal from the reare instead.
If you guys want to use those very long OALs you are starting off with the wrong platform. Mausers are not suited for such long range long cartridge rifles. Not rigid enough.
I would not do it. Many have; successfully. If it sets back, he will know it soon. Not unsafe; just unwise.
Heat treatment costs $175, so it might not be economical to do it for one receiver.
Bolt matching or not, means nothing.
You have a solid .5 probability of success with this one.
I won't comment on the barrel choice.....
I would choose a VZ24 or the like, if you really have to use a Mauser, and do not open it op for the long OAL bullets, and use the 08 for a 7mm. Not mag.
You mentioned several projects; what are the others? Just curious since I have lots of Mausers. Hundreds.

I did a 300 Win. Mag. Mk 248 Mod.1 on a MarkX action with CDI DBM bottom metal.
Overall seated length with a 230 Berger is 3.685
Since it's a center feed out of the AI box it's not necessary to take the whole ramp side to side for that.
Just take enough to clear the bullet nose in the center of the ramp, I used a 3/16 solid carbide end mill for this work.
Also consider going with the MK1-248 chamber and throat (lower initial start pressure do to the long throat and long lead)
As far as case depth on the old '08 I'd get it re-hardened.
As far as bedding, Marine Tex, Devcon liquid steel or Bisonite. from the chamber cylinder to the rear screw, get all the surface area you can get.

just to be "Clear" on marinetex.. ONLY use the gray, as the white is elastic

It is not clear as to whether the action is a 1908 DWM (soft) or a 1935 Mauser (hard). I would not recommend a magnum of any sort on a 1908 but would be OK with a 1935. I do not like to lengthen the mag to any more than about 3.5 although I did so early in my career.
If I wanted to build a 30 cal magnum on a Mauser, I would choose a 308 Norma or 30-338. I have built a few 30 Newtons as well but the brass is a little spendy and not that easy to find. Great cartridge though. Regards, Bill

quote:

Originally posted by Timan:
I did a 300 Win. Mag. Mk 248 Mod.1 on a MarkX action with CDI DBM bottom metal.
Overall seated length with a 230 Berger is 3.685
Since it's a center feed out of the AI box it's not necessary to take the whole ramp side to side for that.
Just take enough to clear the bullet nose in the center of the ramp, I used a 3/16 solid carbide end mill for this work.
Also consider going with the MK1-248 chamber and throat (lower initial start pressure do to the long throat and long lead)
As far as case depth on the old '08 I'd get it re-hardened.
As far as bedding, Marine Tex, Devcon liquid steel or Bisonite. from the chamber cylinder to the rear screw, get all the surface area you can get.

Thanks- great point on just "nosing" the feed ramp.
Once I find out what the cust intends on shooting (could be factory, for all I know) I'll go from there. Regardless, I'm going to keep the feed ramp removal minimal.
Appreciate the input on the Marine Tex...but I'm a 10110 putty fanboy

The other two are Israelis, barrel replacements. Second one is on the way in (haven't seen it yet). He's had these parts for years- no idea where he was able to get take-off's.
First one is done, FN receiver, barrel with a mirror bright bore with sharp lands. Luckily, the new barrel under-clocked by only 1/4 turn so minimal removal of the shoulders was needed. I was concerned about this (still am for the next one) in the event the replacement barrel slightly overclocks. The secondary torque shoulder on the barrel is so thin that I don't think I could take .080 off it and still have it be viable. I puzzled on the setup for a while- lathe spindle at 1-3/8" couldn't accommodate the barrel due to the rear sight base so I set up in the steady. Stuck a dead center in the chamber, muzzle ahead of the front sight in a 6-jaw Buck, put an indicator on the barrel shank between the torque shoulder and sight where the steady would go and there was only .001 TIR on the barrel OD- I was amazed it was that concentric. I have a receiver truing fixture (two spiders) that I also use for "shorty" barrels, but same problem with ID not being able to accommodate because of the rear sight base.

New Israeli barrels were available a few years ago. If you have one with sights already on it (all I got were in the white; no sights), it is easy to move the sight bases after the barrel is tight.They are soldered and have set screws. No need to go to the trouble of cutting the barrel any. Only the inner shoulder should touch on a military barrel anyway.

Everyone has their own methods. I've always followed Kuhnhausen on military barrels, with the tenon being .001 longer than the measurement between the torque shoulders to get them both to draw up. On non-military contours, I don't think it makes a bit of difference whether the primary torque shoulder is used (but I use it anyway). With a trued receiver ring, and a barrel with enough shoulder I don't see a rationale to treat it differently than any other modern bolt gun that shoulders on the receiver ring only.

Not sure what you mean when you say no need to cut the barrel any, but I see it being easier (read- faster) to face the shoulders and deepen the chamber try to re-set both sights precisely to get them clocked (?).

Military barrel shoulders are too small to use as torque shoulders, so that is why the gap is there. As for commercial barrels; I make them fit tight against the inner shoulder, as designed, and less so against the receiver face. But no gap. If you move the barrel off the inner shoulder, you are increasing the brass protrusion from the chamber; a bad thing. Do it as designed.
I find it easier to move the sights (use a level) than setting up and facing off and rechambering; That is just creating work.
I have done it both ways though. But deepening a military chamber can go wrong; they aren't always true to the OD. You will end up with a crooked chamber or a step in it if the original is larger than your reamer. Been there, and got the T shirt on Mausers. .

quote:

Originally posted by Big Gorilla Gunworks:
Customer has dropped off several of his Mauser "projects". One of them is a 98 Brazilian action to have a prefit installed- a McGowen that he's had in .300 Win Mag, together with CDI (DBM) bottom metal to be fitted in a PH Target stock.

Kuhnhausen recommends against using 98 actions for magnum length cartridges due to the significant amount of steel that needs to be removed from the feed ramp. If I were to go with max available with the bottom metal, I'd be milling out roughly the lower/steeper section of the feed ramp completely.


Compared to many here I've got limited experience with the Mauser- are the big bore safari magnums unsafe conversions?

When the small ring and the M98 Mauser was designed, the 6.5 X 55, the 7 X 57 mm, and the 8 X 57 mm service cartridge operated at 3,000 atmospheres, which is approximately 43,371 psia. By the time WW2 rolls around, the German service cartridge was 46,000 psia. Maybe improvements in metallurgy justified this, maybe not.

Early steels are full of residuals that would not oxide, and none of the military Mauser “experts” have provided any material composition analysis for WW1, pre WW2, and WW2 actions. What material analysis from 1890 and WW1 era steels that I have found on the web, show plain carbon steels with material properties inferior to the same steels compositions today. And it is because the steels of that era are loaded up with residuals, slag, and inclusions. No one, and I mean no one, uses those plain carbon steels in a safety critical application, such as a rifle receiver today. Heck, this year I purchases a transmission flex plate for $65.00, called the manufacturer.The Engineer I talked to told me it was made of 4340 steel. Maybe some of the nostalgic old action fan boys ought to call up flexplate manufacturers and convince the metallurgists that 1035 steel ought to be used, because that was what Paul Mauser used in the 1890's.

If the action is in good condition, and headspace is correct, I don’t envision a major risk shooting those old relics with cartridges loaded to a pressure of 43,371 psia or less. However, fan boys chamber these military action in totally inappropriate cartridges, like Ackley Improved rounds, and belted magnums. In terms of pressures, I provide the following as a back of the envelope analysis:

From Cartridges of the World

8 mm case head diameter 0.470” Area 0.1735 square inches
300 Win Mag case head diameter 0.515” Area 0.2083 square inches

Bolt face loads

8mm (Mauser design loads) 0.1735 in ² X 43, 371 lbs/ in ² = 7, 525 lbs
Proof test for older Mausers
308 Win = 0.1735 in ² X

300 Win Mag = 0.2083 in ² X 65,000 lbs/ in ² = 13, 539 lbs

The 300 Win Mag provides an 80% increase in bolt thrust over standard military loads.

[Poo has been tossed at me in this forum for using cartridge OD to calculate bolt thrust. However, none of the poo throwers calculated the cartridge bolt thrust with cartridge ID. OK poo throwers, what case ID should be used?, and what are the numbers? How much does that change in percentage increase in bolt thrust of a 300 Win Mag? ]

I have seen nothing to indicate that Mauser, or Yugoslavia, or FN, or or anyone else who made these Mauser actions built these military actions to a higher pressure standard and a higher load standard. The average pressure did rise by a couple of thousands in WW2, that may have been because the Military was willing to accept a reduced service life, or that they thought improved production processes produced a cleaner steel. But these rifles were made to a price point, by managers who were only interested in meeting the minimum requirements. No one built military actions out of higher grade materials, for higher pressure applications, so one hundred years after the managers and workers passed from this plane, Cults could regularly use 60,000 psia cartridges in the things.

The risks of higher pressure loads is bolt lug cracking and receiver seat set back, and possibly receiver ring cracking. If enough case sidewall is pulled from the chamber, the case head will rupture.

No one, and I mean no one, has addressed Mauser action lifetime with increased pressures. No one has addressed a non destructive method how to do that. None of them has provided material strength data, that is yield and ultimate. None of them has calculated an expected lifetime of lugs, receiver, given the material properties and the use of belted magnum cartridges. Again, something that the action was never designed or built to use. What is bearing capability of the receiver seats after heat treatment? What loads cause receiver seat deformation, and how many dynamic loads will the receiver seats take before deformation? If the receivers are being heat treated to a higher hardness than the original heat treat, the fatigue life will be less. So how many pressure cycles will the bolt lugs take?

This is your risk. You are expected to know this. You are the manufacturer. You took an action, that you assumed was good, that fan boys told you was good, and yet, you actually know little to nothing about that action. And as you will find out, neither do the fan boys. This forum has a large, vocal, Cult built around nostalgia of old rifles. You can stand on the wall of the cemetery, shake your fist at the tombstones, but Paul Mauser does not care, and nor does he have any assists that can be seized. But you do. Strict product liability puts a heavy burden on you, the manufacturer. The standard is know, or should have known. A manufacturer, a seller, or a retailer may be held strictly liable for injuries caused by using a consumer product even if no defects occurred when making or selling that product.

If one of these historic actions fails, causing injury to one of your customers, those friendly relations you had before action failure are going to evaporate fast. A customer with a missing eye, eye socket, or hand, will be reminded every day who built the death trap that blew up in his face.

If you do not understand your risk, or your liability, maybe it is better than you tell the customer you won’t rebarrel any of those actions at all, or at the most, won’t rebarrel to a cartridge whose pressure is higher than what the original military cartridge operated at.

I recommend you get a hobby. It will make you feel better and relive the stress you get from AR. It obviously makes you anxious.

I really enjoyed Slammers latest post, he really has been busy sitting at his computer researching, improving and tweaking his thesis.
Then he is rewarded by cruel people throwing poo at him.
Shameful.
Slammy, don’t be deterred, keep up the hard work, it will pay off in the end.

I'm concerned about his health; all this is going to make him have a coronary. Obviously too much stress, and the monkey poo can't be good, at his age.

Don’t worry, the poo won’t stick, he’s Teflon coated.

quote:

Originally posted by dpcd:
I'm concerned about his health; all this is going to make him have a coronary. Obviously too much stress, and the monkey poo can't be good, at his age.

Former TACOM employee, you are the one with an attachable Government pension. You ought to be more worried, that stack of hundreds of Mauser actions don't represent wealth, they represent risk.

Slamfire, seeing as you are a legal expert as well as a gun expert, maybe you can hop on your computer and find all the examples of Mauser 98’s blowing up in shooters faces and all the ensuing legal actions and prosecutions resulting in guilty verdicts for negligence that you are so obsessed with.
Surely there must be hundreds over the last century.

Yawn!

Slammy is the unwanted gift that keeps giving like herpes.

Wow! this thread disintegrated quickly. It started with such promise, lots of good information disseminated by professional gunsmiths; this is how we lost speerchucker.

This guy who is unwilling or afraid to identify himself needs to read up on his Wittgenstein, as in:

Whereof one cannot speak, thereof one must be silent.

Those who can, do; those who can't, teach.

quote:

Originally posted by SlamFire:
When the small ring and the M98 Mauser was designed, the 6.5 X 55, the 7 X 57 mm, and the 8 X 57 mm service cartridge operated at 3,000 atmospheres, which is approximately 43,371 psia. By the time WW2 rolls around, the German service cartridge was 46,000 psia.

Service cartridges varied depending on countries specified, powder, bullet type, and pressure. Likewise, proof testing varied. Argentine 1891's were originally proofed at 4500 ATM and in 1893 they raised that to 5000 ATM. (Webster p67) 1893's were proof tested at 5600 ATM after it was found loads of 6000 ATM would "dilate" the chamber. (Boado p774/775)

quote:

Originally posted by SlamFire:
Maybe improvements in metallurgy justified this, maybe not.

Both metallurgy and heat treatment more than justified this.

quote:

Originally posted by SlamFire:
none of the military Mauser “experts” have provided any material composition analysis for WW1, pre WW2, and WW2 actions.

It has been published in numerous books. Speed, Karem/Steves, Stankovic/Sheehan, Storz, and more! Try getting OFF the internet and cracking a book?

quote:

Originally posted by SlamFire:
What material analysis from 1890 and WW1 era steels.

Those would be interesting to read, why don't you post links to them.

quote:

Originally posted by SlamFire:
Heck, this year I purchases a transmission flex plate for $65.00, called the manufacturer.

You've claimed this numerous times but won't state the manufacturer or their phone number. I worked in tier 1 automotive and you'll never talk to an engineer and they would never tell you what the flex plate material is and it wasn't 4340. A small boutique manufacturer, maybe. Pleas post the company, phone number, and the engineer you spoke with. I'd like to give them a call.

quote:

Originally posted by SlamFire:
The Engineer I talked to told me it was made of 4340 steel. Maybe some of the nostalgic old action fan boys ought to call up flexplate manufacturers and convince the metallurgists that 1035 steel ought to be used, because that was what Paul Mauser used in the 1890's.

I got bad news for you, a great many of your car's steel components are plain carbon. If you have a transmission, which I am guessing you do (maybe you are more a Tesla guy), the majority of clutch and torque converter components are plain carbon steel.

Do the maths for me on a 7200kgcm2 pressure test. You show the math and I'll show the results.

quote:

Originally posted by SlamFire:
I have seen nothing to indicate that Mauser, or Yugoslavia, or FN, or or anyone else who made these Mauser actions built these military actions to a higher pressure standard and a higher load standard. The average pressure did rise by a couple of thousands in WW2, that may have been because the Military was willing to accept a reduced service life, or that they thought improved production processes produced a cleaner steel. But these rifles were made to a price point, by managers who were only interested in meeting the minimum requirements. No one built military actions out of higher grade materials, for higher pressure applications, so one hundred years after the managers and workers passed from this plane, Cults could regularly use 60,000 psia cartridges in the things.

You do not know much about Mauser do you? You do not know much about how the "Master" system worked? Mauser themselves, the actual mothership company, built factory Commercial Mauser rifles chambered in 60kpsi cartridges. Those cartridges proof at almost 74kpsi.

quote:

Originally posted by SlamFire:
The risks of higher pressure loads is bolt lug cracking and receiver seat set back, and possibly receiver ring cracking. If enough case sidewall is pulled from the chamber, the case head will rupture.

The bolt lug will crack, though typically that requires a very hard bolt lug. Likewise, the receiver ring rarely crack, they typically balloon. Remember, you said these things were improperly heat treated steel that was lower quality than a hardware store chinese bolt.
Mocking your absurdity aside, failures typically are well contained even at high pressure. When you go north of 80kpsi the brass of the exposed case head starts to flow. After repeated firings of mid to high 80's typically one of the "stand offs" will break, usually the lower one. Using a factory bolt and receiver, after about 30 rounds of 70-80 kpsi rounds, headspace grew a few thousandths, which was chamber growth. It wasn't until a projected load of 102,000 psi (mapped at 87kpsi due to gauge limitations) that the case head flowed completely out of place, broke a standoff, and set back into the receiver abutments. The extractor remained intact, and no components were broken. Headspace grew (chamber growth and set back) from closing on a NOGO to closing on a FIELD. Action is still usable, and will be used to do high pressure development for extreme failure.

quote:

Originally posted by SlamFire:
No one, and I mean no one, has addressed Mauser action lifetime with increased pressures. No one has addressed a non destructive method how to do that. None of them has provided material strength data, that is yield and ultimate. None of them has calculated an expected lifetime of lugs, receiver, given the material properties and the use of belted magnum cartridges. Again, something that the action was never designed or built to use. What is bearing capability of the receiver seats after heat treatment? What loads cause receiver seat deformation, and how many dynamic loads will the receiver seats take before deformation? If the receivers are being heat treated to a higher hardness than the original heat treat, the fatigue life will be less. So how many pressure cycles will the bolt lugs take?

I am not sure whether you do not understand what this actually means, or you have no concept as to the cost necessary to complete this. If you'd like to bank roll it, I'll put it together.

quote:

Originally posted by SlamFire:
This is your risk. You are expected to know this. You are the manufacturer. You took an action, that you assumed was good, that fan boys told you was good, and yet, you actually know little to nothing about that action. And as you will find out, neither do the fan boys. This forum has a large, vocal, Cult built around nostalgia of old rifles. You can stand on the wall of the cemetery, shake your fist at the tombstones, but Paul Mauser does not care, and nor does he have any assists that can be seized. But you do. Strict product liability puts a heavy burden on you, the manufacturer. The standard is know, or should have known. A manufacturer, a seller, or a retailer may be held strictly liable for injuries caused by using a consumer product even if no defects occurred when making or selling that product.

You didn't work in manufacturing did you?

quote:

Originally posted by SlamFire:
If one of these historic actions fails, causing injury to one of your customers, those friendly relations you had before action failure are going to evaporate fast. A customer with a missing eye, eye socket, or hand, will be reminded every day who built the death trap that blew up in his face.

Have you ever blown up a Mauser action to see what happens? I've seen some catastrophic failures posted online, the majority of them have to do with firing the wrong cartridge in a gun. I can tell you from experience that a Mauser does not grenade. I can tell you from experience that if you blow up a Mauser, you have not made a small mistake.

I presume you mean to insult me when you call me a cultist, which I don't understand. Your irrational delusions seem to be very cult like to me, ignoring what IS. Ignoring what IS in front of you. You even ignored the "cultists" who for the most part recommended AGAINST the conversion. This is the completely irrational part.
dpcd of all people said

quote:

Originally posted by dpcd:
I would not do it

Satterlee even recommended a chamber and throat to reduce pressure.

I cannot imagine being so scared of risk as to say the mere ownership of mauser actions is a risk. Your irrationality is absurd. Do you venture out of your home? I hope not! The risk is far too great. I hope you don't have a basement, the risk is FAR TOO GREAT. You should look up the numbers of people who die because of stairs every year. I hope you don't have a bath tub. Do you? A staggering number of people die in their bath tub every year. If you have one you should probably remove it. The risk is far too great. Have you done a full risk analysis of your home? I can't imagine you using that flex plate you bought, that would be far too risky to take a vehicle out on the road.

Your life is yours. Rise up and live it.

Standing Ovation and resounding applause.

quote:

Originally posted by dpcd:
Standing Ovation and resounding applause.

An Oscar winner.

Spreadsheets don't copy and paste very well here!

If we can accept that Lilja is a credible source, the I used the following formula's to calculate for a Mauser 98.
https://riflebarrels.com/a-look-at-bolt-lug-strength/

For the following I have included the material properties that none of the Mauser "experts" have provided. This material is St C 35.61 DIN 1661, which is one material Mauser used to make bolts. There were several materials used depending on what was specified by the contract or customer.

MAUSER 98
LS=(L*LL*NL*YS)/2 
Where:
LS is the calculated lug shear strength
L is the length of the arc segment 0.463
LL is the axial length of the lugs 0.371
NL is the number of lugs on the bolt 2
YS is the yield strength of the material the lugs are made from 46937
LS = 16125.0186
As mentioned, this number is then divided in half for a safety margin of two. 8062.509301


yield strength kg/mm2 minimum tensil strength kg/mm2 stretch at least

5% 10%
35.61 annealed 28 50-60 23 19
hardened and tempered 33 55-65 22 18
psi psi
annealed 39825 78228
hardened and tempered 46937 85340

THRUST=AREA*CPSI 8032.7 (dcpd caught my mistake, this should be pounds force, not psi)
PSI 69000

Where:
AREA=3.1416*(HS/2)^2
HS=the diameter of the inside of the case head.

If we accept Lilja's formula's as acceptable, we can see that based on 35.61 material, a Mauser bolt should be able to experience a 69,000 psi load without any failure. This is at an unknown harden and temper spec and based on minimum yield strength requirement.

If instead we used the material in the annealed condition, with a yield strength of 39825, with a resulting lug shear strength of 6840 pounds force, we can by a safety margin of two shoot a 58,000 psi cartridge with a thrust of 6752 pounds force.

I, for one, appreciate Slamfire's posts...That way when FalGrunt responds I can actually learn something Thanks for taking the time Mr. Myers.

quote:

Originally posted by MNR:
I, for one, appreciate Slamfire's posts...That way when FalGrunt responds I can actually learn something Thanks for taking the time Mr. Myers.

Best post ever!!!!!!!

DPCD and FAL Grunt have my support. I will put my money on their experience anytime.

I have been avoiding posting as I do not like pouring gas on a fire, but a little info from my playing with Mausers.

This one has been over 60,000 psi many times with no ill effects. 60,000 psi is too high for me in a daily user, but this action is used in developing loads for non standard cartridge's that I fool with. Shown with a 50 cal that puts out around 5000 ft lbs at a reasonable pressure.



I used the Oehler M43 for testing. Good stuff!





Yes Virginia, we did use a lanyard and hid behind the pickup when touching off!!!



The 50 cal rifle the loads were developed for:



Tooling made in the shop for the 50 cal



Reamers, parts, dies and die blanks



Back to the OP question, nope, I do not like grinding of the lower lug in Mausers to fit longer cartridges. Sure, it has been done by a lot of folks but this does not make it correct in my opinion. Paul Mauser made the Magnum Mauser action for this purpose. And I have a factory made Whitworth 375 H&H, with the lower lug ground away, all work done at Manchester.

quote:

Originally posted by SlamFire:
blah blah blaaaaa

Doug, is this you?

Just read this today:

Pressures, Case Strength and Back Thrust
https://www.longrangehunting.c...and-back-thrust.396/

I have the remains of a Mauser M98 action that was totally destroyed with a standard loaded .22-250 cartridge when the headspace became too long, allowing the case to separate. The brass cartridge head was welded into the ejector slot in the locking lug and part of the case body at the end of the web area expanded and formed between the bolt face and the butt of the barrel in a tight manner, looking a lot like it had been melted and poured into the gap. I had to remove the barrel in order to open the action. Incidentally, the shooter ended up in the hospital emergency room for removal of metal and carbon fragments, his eyes being saved by the glasses he was wearing. All of this was brought about by the failure of the brass case when the soft M98 locking lug seats finally pounded back far enough to make the headspace too long. Perhaps I should add here that Mauser actions are not heat treated like our modern factory actions. They are made from relatively soft carbon steel and then only surface hardened, case hardened, for a very thin, hard surface. When these M98s are reconditioned many shops will lap the locking lugs and often will cut the thin, hard surface completely away, leaving only the soft carbon steel underneath to hold the pounding of the bolt locking lugs in the future. They will pound back over a period of time resulting in too much headspace and a wrecked rifle...or worse.

I am trying to be helpful for some one building high power rifles around these cartridges, in warning him about his potential liability. If a customer sues, none of the fan boys are going to financially pitch in, and bail him out of his costs. What would be his defense be when it is known that the action he used, is chambered in a cartridge that operates above the proof pressures of the original action?

quote:

If we accept Lilja's formula's as acceptable, we can see that based on 35.61 material, a Mauser bolt should be able to experience a 69,000 psi load without any failure. This is at an unknown harden and temper spec and based on minimum yield strength requirement.

If instead we used the material in the annealed condition, with a yield strength of 39825, with a resulting lug shear strength of 6840 pounds force, we can by a safety margin of two shoot a 58,000 psi cartridge with a thrust of 6752 pounds force.

It is optimistic to use modern material data to predict the strength of historic actions. You need to know what the actual strength of the material was, and is, in the historic action being converted. The older the mechanical object, the more you actually have to know, because processes varied so much.

Safety factors always muddy the waters. Claiming that safety factors mean something is twice as strong as needed, is a mis use of safety factors. Might have been true when the part was new, but even then, not necessarily true the part was twice as strong as design requirements. Variations in materials, heat treatment, fitment, etc are in those safety factors. Lug to receiver seat contact are not going to be perfect or necessarily symmetrical, which is why gunsmiths true actions. And then with use, materials degrade. What would have taken a load of two when new, might just fail with a load of a half with use. Safety factors, lets say two, are there in the hope the mechanical items with a safety factor of two, will survive a lifetime of one.

Two firemen fell to their deaths with ropes that had a safety factor of 10:1. The standard was raised to 15:1. https://www.firehouse.com/resc...he-importance-of-151 So, anyone want to be repelled out of a ravine with a rope system with a safety factor of two, or one?

Heat treatment may put the fatigue clock back to zero, I really don't know this, but it won't take the slag and inclusions out. Those historic actions will retain all the garbage residuals in their matrix that they always had. I did ask, how does a heat treater take into account all those residuals when heat treating an action. Never got a reply. And, if there are internal cracks, flakes, cold shuts, etc, will heat treatment fix those?

Incidentally, the 58,000 psia number is interesting. What would that be, same thickness, proper heat treatment, with a decent alloy steel. Lets say, 4140 or 4340? The 69,000 psia number is also interesting, as someone using a cartridge whose pmax average is 65,000 psia is operating very close to a calculated load limit. And that calculation assumes, modern materials, and perfect materials.

And then, what is the fatigue lifetime? Everyone calculates pressures based on theoretical one shot destructive tests, but how many 58 kpsia, or 69 kpsi rounds, should someone expect a vintage M98 bolt to last? Would it be 100 rounds, or 200 rounds, or 1000 rounds?

A comment, just who uses pressure gauges and uses them during load development? Reloaders just add powder until they get sticky bolt lift and/or blown and leaking primers. A gunsmith I know told me of the number of Rem M700’s he received with broken bolt handles. Reloaders created such high pressure rounds, they could not open the bolt. So they got a block of wood and beat on the bolt handle till it snapped off. The gunsmith said he had to take the barrel off, because the case has flowed into the bolt face. What will those sort of loads do to a military Mauser action?

There is incidentally, a Wiki article on the Weatherby MKV action. Weatherby tested it to 200,000 CUP without action failure. https://en.wikipedia.org/wiki/Weatherby_Mark_V I would feel safer with the stronger action.

quote:

Likewise, proof testing varied. Argentine 1891's were originally proofed at 4500 ATM and in 1893 they raised that to 5000 ATM. (Webster p67) 1893's were proof tested at 5600 ATM after it was found loads of 6000 ATM would "dilate" the chamber. (Boado p774/775)

Is this the José Boado y Castro who was writing books in Spanish in the 1890s? He wrote several. Which one are your referring to?

The proof pressures you describe could be, the M1903 was proof tested at 70 K, but proof testing at 82,000 psia is fantastical.
4500 atm 66131.77 psia
5000 atm 73,000 psia
5600 atm 82,000 psia

These are my sources, authors who are a bit later in vintage.

Rifle Magazine Issue 159 May 1995 Dear Editor pg 10
http://www.riflemagazine.com/m...PDF/ri159partial.pdf

quote:

Ludwig Olsen :

Mauser 98 actions produced by Mauser and DWM were proofed with two loads that produced approximately 1000 atmosphere greater pressure than normal factory rounds. That procedure was in accordance with the 1891 German proof law. Proof pressure for the Mauser 98 in 7 X57 was 4,050 atmospheres (57, 591 psi). Pressure of the normal 7 X 57 factory load with 11.2 gram bullet was given in Mauser’s 1908 patent boot as 3,050 atmosphere, or 43, 371 pounds.

While many Mausers in the 1908 Brazilian category will likely endure pressures considerably in excess of the 4,050 atmospheres proof loads, there might be some setback of the receiver locking shoulder with such high pressures

Kunhausen shows similar numbers in his book : “The Mauser Bolt Actions, A Shop Manual”

Rifle & Carbine 98: M98 Firearms of the German Army from 1898 to 1918 Dieter

M98 Mauser service rifles underwent a 2 round proof at 4,000 atm gas pressure, 1 atm = 14.6 psi, 4000 atm = 58, 784 psia. Page 103. A comment on the metallurgy and process technology of the era, Dieter found records that indicated that the bolt lugs broke on 1:1000 of GEW98 service rifles used by the Bavarian Army Corp!

Gun Digest 1975 has an excellent article, “A History of Proof Marks, Gun Proof in German” by Lee Kennett.

quote:

“The problem of smokeless proof was posed in a dramatic way by the Model 1888 and it commercial derivates. In this particular case a solution was sought in the decree of 23 July 1893. This provided that such rifles be proved with a government smokeless powder known as the “4,000 atmosphere powder”, proof pressure was 4,000 metric atmospheres or 58,000 psia. The 4000 atmosphere proof was standardized for the 1893 and continued after 1911.

Anyway, later.

!!!NEWS FLASH!!! 22.250 handloader has a CHS in his lapped and set back Mauser!!!
Again anecdotal evidence of poor Mauser metallugy from the internet.
Still no mention of the nut behind the butt.
See ya.

quote:

Originally posted by SlamFire:

I am trying to be helpful for some one building high power rifles around these cartridges, in warning him about his potential liability. If a customer sues, none of the fan boys are going to financially pitch in, and bail him out of his costs. What would be his defense be when it is known that the action he used, is chambered in a cartridge that operates above the proof pressures of the original action?

I applaud anyone wishing to be helpful. Ranting about the end of the world and that the sky falling is hardly helpful. Re READ that above posts by everyone, including the, as you call them, cultists, advised AGAINST building a 300 Win mag on a 1908 Brazilian.

The example you give is an excellent case as to why you shouldn't have someone who is ignorant about Mauser's build a Mauser. Just like your previous example of putting a small block chevy in a beetle. It also points to an extremely ignorant shooter who did not notice that his headspace grew enough to have a case head separation. (This is no SMALL amount)

Finally, I have several friends who build rifles on Remington 700's, Stillers, Kelbly's, etc whose cartridges FAR exceed the original "proof" pressure. Why are you not posting extensively about the dangers of using Remington 700's? I have seen more damaged modern guns due to these guys running ridiculous pressures to eek a few more 100 fps to hit that target at 2100 yds, than I have in Mauser's running 22-250.

quote:

Originally posted by SlamFire:
It is optimistic to use modern material data to predict the strength of historic actions. You need to know what the actual strength of the material was, and is, in the historic action being converted. The older the mechanical object, the more you actually have to know, because processes varied so much.

That is why I posted the specifications from 1937.

quote:

Originally posted by SlamFire:
Safety factors always muddy the waters. Claiming that safety factors mean something is twice as strong as needed, is a mis use of safety factors. Might have been true when the part was new, but even then, not necessarily true the part was twice as strong as design requirements. Variations in materials, heat treatment, fitment, etc are in those safety factors. Lug to receiver seat contact are not going to be perfect or necessarily symmetrical, which is why gunsmiths true actions. And then with use, materials degrade. What would have taken a load of two when new, might just fail with a load of a half with use. Safety factors, lets say two, are there in the hope the mechanical items with a safety factor of two, will survive a lifetime of one.

Then un muddy the waters. You consistently present a slippery slope of ever changing conditions that are unmeetable. You act like the idiot engineers I worked with who refused to see literal physical evidence of their failures piled in a heap in front of them. Or the engineers who were to scared to take responsibility for their own actions who would "condition" any explanation away so as not to be blamed when something failed.

quote:

Originally posted by SlamFire:
Two firemen fell to their deaths with ropes that had a safety factor of 10:1. The standard was raised to 15:1. https://www.firehouse.com/resc...he-importance-of-151 So, anyone want to be repelled out of a ravine with a rope system with a safety factor of two, or one?

Yes, yes, and steel with ridiculous safety factors still fail, and the concrete with insane safety factors still fail, and I still drive on bridges and roads. I still inspect my car, and my ropes, and my firearms.

quote:

Originally posted by SlamFire:
Heat treatment may put the fatigue clock back to zero, I really don't know this, but it won't take the slag and inclusions out. Those historic actions will retain all the garbage residuals in their matrix that they always had. I did ask, how does a heat treater take into account all those residuals when heat treating an action. Never got a reply. And, if there are internal cracks, flakes, cold shuts, etc, will heat treatment fix those?

I just went through your post, again, I did not see that question. Heat treat will not remove residuals. I'd love to see your analysis that shows the residuals, slag and inclusions.

quote:

Originally posted by SlamFire:
Incidentally, the 58,000 psia number is interesting. What would that be, same thickness, proper heat treatment, with a decent alloy steel. Lets say, 4140 or 4340? The 69,000 psia number is also interesting, as someone using a cartridge whose pmax average is 65,000 psia is operating very close to a calculated load limit. And that calculation assumes, modern materials, and perfect materials.

Like all engineering, it assumes something that doesn't exist.

quote:

Originally posted by SlamFire:
And then, what is the fatigue lifetime? Everyone calculates pressures based on theoretical one shot destructive tests, but how many 58 kpsia, or 69 kpsi rounds, should someone expect a vintage M98 bolt to last? Would it be 100 rounds, or 200 rounds, or 1000 rounds?

As I mentioned in my last post, if you want to bank roll it, I will find you the answers. I know that the k98k action I used for initial baseline and testing had about 50 rounds ranging 60kpsi up into the low 80's before the headspace started to grow. Mine you, that was NOT the receiver or bolt, but the chamber stretching. In every test I have done so far, that BARREL stretches before the receiver or bolt show any damage.

quote:

Originally posted by SlamFire:
A comment, just who uses pressure gauges and uses them during load development? Reloaders just add powder until they get sticky bolt lift and/or blown and leaking primers. A gunsmith I know told me of the number of Rem M700’s he received with broken bolt handles. Reloaders created such high pressure rounds, they could not open the bolt. So they got a block of wood and beat on the bolt handle till it snapped off. The gunsmith said he had to take the barrel off, because the case has flowed into the bolt face.

Well... several of the guys I know use pressure systems of one or another. I guess about 50%.
Fun fact I bet you did not know, going off of your post. Flattened primers, loose primers, and sticky bolts are not a good indicator of pressure.

quote:

Originally posted by SlamFire:
What will those sort of loads do to a military Mauser action?

What sort of loads are they? Which Military Mauser action? A Mauser 98 will open a high pressure load that a Remington 700 won't. Remington's extraction is terrible, and that is the reason most people replace and retime the bolt handle. In my previous post, I mentioned a 100kpsi round that clocked in a 87kpsi. A couple light taps with a rawhide hammer opened the bolt. This was primarily because the brass had flowed to prevent it from rotating.

quote:

Originally posted by SlamFire:
There is incidentally, a Wiki article on the Weatherby MKV action. Weatherby tested it to 200,000 CUP without action failure. https://en.wikipedia.org/wiki/Weatherby_Mark_V I would feel safer with the stronger action.

Great, use a Weatherby then. Mauser tested the Mauser 98 action to extreme failure too, but you won't accept any other primary documents, so I don't see why you would accept that.

quote:

Likewise, proof testing varied. Argentine 1891's were originally proofed at 4500 ATM and in 1893 they raised that to 5000 ATM. (Webster p67) 1893's were proof tested at 5600 ATM after it was found loads of 6000 ATM would "dilate" the chamber. (Boado p774/775)

quote:

Originally posted by SlamFire:
Is this the José Boado y Castro who was writing books in Spanish in the 1890s? He wrote several. Which one are your referring to?

Fabricacion De Fusiles
If you know Boado, 90% of your issues are discussed in literally hundreds of pages dedicated to the composition of the steel, the heat treat, the mechanical properties, all aspects. Even discussion of what the different alloying aspects did and why certain properties were important. This includes the tools, gauges, and machines for testing. All most all of this information came directly from Loewe, DWM, FN and other major makers.

quote:

Originally posted by SlamFire:
The proof pressures you describe could be, the M1903 was proof tested at 70 K, but proof testing at 82,000 psia is fantastical.
4500 atm 66131.77 psia
5000 atm 73,000 psia
5600 atm 82,000 psia

Fantastic is right. Amazing what man can do with steel.

quote:

Originally posted by SlamFire:
These are my sources, authors who are a bit later in vintage.

Rifle Magazine Issue 159 May 1995 Dear Editor pg 10
http://www.riflemagazine.com/m...PDF/ri159partial.pdf

quote:

Ludwig Olsen :

Mauser 98 actions produced by Mauser and DWM were proofed with two loads that produced approximately 1000 atmosphere greater pressure than normal factory rounds. That procedure was in accordance with the 1891 German proof law. Proof pressure for the Mauser 98 in 7 X57 was 4,050 atmospheres (57, 591 psi). Pressure of the normal 7 X 57 factory load with 11.2 gram bullet was given in Mauser’s 1908 patent boot as 3,050 atmosphere, or 43, 371 pounds.

While many Mausers in the 1908 Brazilian category will likely endure pressures considerably in excess of the 4,050 atmospheres proof loads, there might be some setback of the receiver locking shoulder with such high pressures

Kunhausen shows similar numbers in his book : “The Mauser Bolt Actions, A Shop Manual”

Rifle & Carbine 98: M98 Firearms of the German Army from 1898 to 1918 Dieter

M98 Mauser service rifles underwent a 2 round proof at 4,000 atm gas pressure, 1 atm = 14.6 psi, 4000 atm = 58, 784 psia. Page 103. A comment on the metallurgy and process technology of the era, Dieter found records that indicated that the bolt lugs broke on 1:1000 of GEW98 service rifles used by the Bavarian Army Corp!

Gun Digest 1975 has an excellent article, “A History of Proof Marks, Gun Proof in German” by Lee Kennett.

quote:

“The problem of smokeless proof was posed in a dramatic way by the Model 1888 and it commercial derivates. In this particular case a solution was sought in the decree of 23 July 1893. This provided that such rifles be proved with a government smokeless powder known as the “4,000 atmosphere powder”, proof pressure was 4,000 metric atmospheres or 58,000 psia. The 4000 atmosphere proof was standardized for the 1893 and continued after 1911.

Olsen's book is rife with errors. Storz work is well done, with cited primary sources. He also does an excellent job of analyzing his sources. So, you would put faith in Olsen, who could have written a stunning work based on primary sources, over someone like Storz, who did work from primary sources. Put another way, you would take a secondary source, like Olsen, over an original manufacturing document?

Finally, you have to differentiate between commercial proofing and military proofing. They were different standards. Military contracts were proofed to the specifications of the contract.

I'd recommend finding better PRIMARY sources, or at least more contemporary works that use primary sources (like storz, speed, karem/steves, etc)

quote:

Originally posted by SlamFire:
Dieter found records that indicated that the bolt lugs broke on 1:1000 of GEW98 service rifles used by the Bavarian Army Corp! [/i]

Why don't you include the rest of the findings....

quote:

Originally posted by dpcd:
Standing Ovation and resounding applause.

quote:

Originally posted by rcraig:
An Oscar winner.

quote:

Originally posted by MNR:
I, for one, appreciate Slamfire's posts...That way when FalGrunt responds I can actually learn something Thanks for taking the time Mr. Myers.

quote:

Originally posted by WoodHunter:
Best post ever!!!!!!!

Thanks guys, I really appreciate it. I'm always happy to share what I know, so if you have question's, don't hesitate to speak up.

Lets try some primary documents along with some other photo's. Everything I will post was; sent to me personally by Jon Speed, or is used with his permission, my own collection, my own photographs, or I will post the ownership.

This document is the 1933 contract with Argentina. It shows both the composition and mechanical properties of the steel for the barrels. Of note, 1.8%-2.9% Wolfram content. And of course, tested to 5000 ATM.

(Jon Speed Collection)

Here is a quick collection of Documents that I grabbed because they were the first I found. Paraguayan Standard Modell contract from 1931/1932. Service cartridge was 3200 ATM, completed rifles were proofed at 4400 ATM, barrel steel proofed at 5600 ATM. Note that is different than the previously specified Argentine contract.

Notes in italics by Jon Speed



Mauser letter to I. G. Farben notified them that barrel proof tests were run at 5600 ATM as they worked directly with Ammo firms to make Proof loads etc.



Standard Modell Spec data Ammo - 7.65
note 3200 ATM



Cover title of Mauser Material barrel test done at Stuttgart Tech School. In Most contracts even small like this one the buyer Wanted a 3rd party to run Main tests like Proofing of Materials even though Mauser ran all their own tests as well.



Inside page shows Crown/U Proof

If you appreciate my posts, and want to learn more, and want to support my research, please consider buying a copy of my booklet titled

Mauser Heat Treat in Brief

I'll be taking orders for a couple/few weeks before I get the first batch printed up.