What's the deal with M96 Mausers being chambered in .30-06?

[p.Rundle]

Hey folks, so I've been seeing a ton of M96 Mausers chambered in .30-06 (and 8x57) recently. I did some research, and saw a variety of people saying that the actions were too weak for the cartridge, or too short, and to just not do it. They claim that the rifles will blow up eventually, and they are not made for a steady diet of the higher PSI of .30-06 than 6.5x55. This seems odd to me because I've also seen a lot of 1893 Mausers (the M1916 carbines) rechambered to 7.62x51. Maybe that's crazy too?

Obviously they aren't as rugged as a large ring 98, but are they that much weaker? Seems weird that so many professional gunsmiths would convert guns to an unsafe caliber. Have there been any changes in peoples perceptions since the last posts I saw on this in like 2012? I am no expert on small rings, so it would be good to learn a bit more from the folks on here. Any input is appreciated.

 

[Potashminer]

Might be able to find a thread I started about this a few years ago. I had bought a STIGA brand 30-06. I got investigating - was made from an ex-military Swede M94/96/38 receiver, with a M94 (likely) bolt and a possibly Danish (?) barrel. Also has the "Nitro test" proof marks. To me that was key - when receiver was re-barrelled, that bolt, receiver and barrel got the "blue pill" - CIP in Europe sets how much over pressure that proof load is - I do not think Sweden joined C.I.P. but follow similar, if not identical, rules. Not required here in North America, usually. Anyone can screw a 30-06 barrel into any receiver and throw on any bolt that looks like it might fit - of unknown background, and never pressure tested to any standard - and can try to sell it to someone. About the third buyer down the line will have no clue what it is that he has bought.

Also, I was told, I think here on CGN, that the STIGA throats are unusually long for a 30-06 - that is one way to limit or control breech pressures - Roy Weatherby was using the concept for his early "boomers". So, I no longer have any doubts or worries about that STIGA 30-06 rifle here. I am quite certain it will handle CIP / SAAMI pressure levels for the 30-06, as long as I need it to.

Magazine length can be a thing. Many Swedes are a bit short to accept some factory 30-06 rounds. This rifle had the Swede military magazine lengthened to accommodate that. Might be why the swap to 8x57JS might be just a bit easier - I think all cartridges will fit, as is.

 

[bearhunter]

Just to add a bit to Potashminer's excellent info, Swede steel is supposed to be a bit stronger than the other steels available at the time they were built.

Even the early 94s were supposedly built on Swede produced steel, which has a higher nickel content etc.

The rifles will easily accept "factory" ammo and handloads up to 48k psi.

Nato spec for them is around 47,600psi.

Many 91/93/95 actions are built for cartridges developing slightly less than 45kpsi and the nations that converted them to 7.62x51 felt they were strong enough for the cartridge, even with military abuse. They did a lot of testing and usually were pretty careful about selecting the better actions they had for the conversions.

Those conversions weren't just hap hazard attempts to create more powerful rifles. They were however cheap interim arms to safely train and fulfil their needs until they could modernize their arms.

In the case of the Spanish conversions, they went to what appeared to be a 7.62x51 Nato cartridge but was designated 7.62 CETME. This cartridge developed similar 48k psi but used a 112 grain bullet.

Supposedly the rifles will work within safe limits, if the pressures don't exceed Nato specs.

 

[zuke]

This has answered a lotta question's I had

 

[Hitzy]

Issue isn't the receiver strength with 96's, it's the lack of gas handling in the event of case failure.
For the 30'06 conversions, it's more involved then just extending mag length, the metal behind the lower reciever lug has to be removed for the cartridge to feed, this weakens the lower lug as a fair amount of metal needs to be removed.
For an extra $100 you can get an HVA 98 or 1600 or PH 98 in 30'06 that would be a much better option.

 

[Potashminer]

Yes. Consider though - the gas handling "system" in a Swede M96 does not strike me as a lot different than found on a Winchester Model 70. But, for sure, was a "real" issue when using ammo produced in 1800's and early 1900's - apparently was a regular occurrences to have cases let go when fired. That flange on the M98 bolt shroud would make considerable difference to the shooter, I would think.

If metal is removed from behind the lower receiver recess to accommodate the 30-06 length, I believe similar was done to get some longer magnums, like 375 H&H, to work within standard 98 Mauser actions. So, to my mind, the "proof testing" step becomes even more important. But I agree - Hitzy's suggestions for appropriate actions for 30-06 are right on. Might have been a thing in 1950's to "make do" and try to use the very inexpensive Swede rifles to make into something else, but no real good reason to be doing that today??

 

[Potashminer]

...

In the case of the Spanish conversions, they went to what appeared to be a 7.62x51 Nato cartridge but was designated 7.62 CETME. This cartridge developed similar 48k psi but used a 112 grain bullet.

...

I had been reading similar, and then contradictory accounts of that on Internet. For sure, Spain was attempting to produce a semi-auto, or perhaps, a select fire infantry arm - was designated as a Cetme - perhaps the brand or name of the maker. They were having difficulties - so resolved in the short term, by creating a cartridge the same size as a 7.62 NATO, but they designated the cartridge as 7.62 Cetme. It does not help matters how they marked their conversions!!! I have a Guardia crested conversion here - it simply says "7.62" on the side - does not mention "NATO" or "Cetme". Also have to remember that for many years a "7.62" was referring to what we call a 30-06 - the 7.62x63. I have no doubt whatsoever that the "lighter" Cetme cartridges were used in those 7.62 conversions, because that ammo was available for the semi-auto / select fire experiment.

It might be splitting hairs, but the Spanish did not convert to "308 Win" - they converted to 7.62 NATO. It seems to have been North Americans who started referring to it as a "308 Win" conversion, because a 308 Win fits into it. Referring to the rifle as a "308 Win" does not make it into one - it was made as a 7.62 NATO - even though there may not be a significant difference. Sorta like North Americans calling the cartridge an "8x57" - there is a low energy "8mm Mauser" named by SAAMI, and there is the standard pressure 8x57 JS (or IS) named by CIP. The German military probably referred to it as a 7.92x57, or 7.9x57 - you will see that on many WWII mausers "7.92" or "7.9" - appears to be North Americans that created the "8x57" name for it, but I do not know that for certain.

I have not found the rest of this booklet - so just the cover page shown below, and the page 5, for some reason. I am not a Spanish speaker, but I think I can piece out that the Spanish military was converting those things from 7mm (7x57) to the 7.62 NATO spec. Those were original 7x57 barrels. Bored out and re-rifled to 30 caliber. You can measure the shoulder on the barrel - much thinner than on the original - so the barrel had been "set back" enough to allow a 7.62 reamer to clean out the longer 7x57 chamber. You see that "gap" within the inletting in those stocks - the barrel has been set back into the receiver when it was re-bored and re-chambered.

 

[p.Rundle]

Thanks for the responses so far boys. Super helpful.

Might be able to find a thread I started about this a few years ago. I had bought a STIGA brand 30-06. I got investigating - was made from an ex-military Swede M94/96/38 receiver, with a M94 (likely) bolt and a possibly Danish (?) barrel. Also has the "Nitro test" proof marks. To me that was key - when receiver was re-barrelled, that bolt, receiver and barrel got the "blue pill" - CIP in Europe sets how much over pressure that proof load is - I do not think Sweden joined C.I.P. but follow similar, if not identical, rules. Not required here in North America, usually. Anyone can screw a 30-06 barrel into any receiver and throw on any bolt that looks like it might fit - of unknown background, and never pressure tested to any standard - and can try to sell it to someone. About the third buyer down the line will have no clue what it is that he has bought.

Also, I was told, I think here on CGN, that the STIGA throats are unusually long for a 30-06 - that is one way to limit or control breech pressures - Roy Weatherby was using the concept for his early "boomers". So, I no longer have any doubts or worries about that STIGA 30-06 rifle here. I am quite certain it will handle CIP / SAAMI pressure levels for the 30-06, as long as I need it to.

Magazine length can be a thing. Many Swedes are a bit short to accept some factory 30-06 rounds. This rifle had the Swede military magazine lengthened to accommodate that. Might be why the swap to 8x57JS might be just a bit easier - I think all cartridges will fit, as is.

Awesome I'll check into it, thanks! I agree that a nitro proof test is certainly a good thing.

Issue isn't the receiver strength with 96's, it's the lack of gas handling in the event of case failure.
For the 30'06 conversions, it's more involved then just extending mag length, the metal behind the lower reciever lug has to be removed for the cartridge to feed, this weakens the lower lug as a fair amount of metal needs to be removed.
For an extra $100 you can get an HVA 98 or 1600 or PH 98 in 30'06 that would be a much better option.

I have a line on one of these M96 .30-06s for $150, in alright condition. It's a bit beat up, but it's a Carl G, so that's kinda neat to me. I definitely don't like the weakened lower lug, however. That is not good lol. What that tells me is that even if I got a new barrel for 6.5x55 the receiver is permanently compromised, to some degree or another.

 

[tiriaq]

In Jerry Kuhnhausen's book on the Mauser, he expresses concern about 98s being converted to .375H&H because of what happens to the receiver behind the lower locking abutment.
Keep in mind that PH, Zastava, and others made .375s in standard length 98 actions.
If one of these rifles - like those being sold by TradeEx - was made up commercially in Sweden, I wouldn't worry about a 96 in .30-06 or 8x57.
In the event of a case failure, a 98's gas handling is superior to the earlier Mausers, and to many current production sporting rifles. A 98 does have safety breeching, not quite up to the standard of the Remington 700, but still excellent.
I don't think I would pick a vintage '96 actioned sporter if I was going to hotrod handloaded rounds, use with commercial equivalent loads one should be just fine.

 

[p.Rundle]

In Jerry Kuhnhausen's book on the Mauser, he expresses concern about 98s being converted to .375H&H because of what happens to the receiver behind the lower locking abutment.
Keep in mind that PH, Zastava, and others made .375s in standard length 98 actions.
If one of these rifles - like those being sold by TradeEx - was made up commercially in Sweden, I wouldn't worry about a 96 in .30-06 or 8x57.
In the event of a case failure, a 98's gas handling is superior to the earlier Mausers, and to many current production sporting rifles. A 98 does have safety breeching, not quite up to the standard of the Remington 700, but still excellent.
I don't think I would pick a vintage '96 actioned sporter if I was going to hotrod handloaded rounds, use with commercial equivalent loads one should be just fine.

that's great to know, I appreciate the input tiriaq

 

[Potashminer]

Picture below - the upper receiver is a more or less unmolested Husqvarna that came to me with an 8x57 barrel - so from a Husqvarna Model 648. The lower one is that STIGA 30-06. Top one, which I am quite sure is not ground behind the lower lug, measures about 0.900" from front edge of magazine well to the recoil shoulder on the receiver. The lower one, adapted for 30-06, measures about 0.750" from front of magazine opening to the receiver recoil lug. The modified Swede magazine for 30-06 measures 3.37" inside length - and appears to all have been done by extending the front end forward - rear end appears original and unmolested.

 

[MiG25]

For what it's worth, in their Gunbug Guide from the 1960's, Norma takes the 6.5x55 to 49,600 psi, which is higher than they take the 30-06, 8x57, and 308 Winchester. They make no caveats about 96 vs 98 actions.

 

[p.Rundle]

For what it's worth, in their Gunbug Guide from the 1960's, Norma takes the 6.5x55 to 49,600 psi, which is higher than they take the 30-06, 8x57, and 308 Winchester. They make no caveats about 96 vs 98 actions.

I'm no reloader, but wikipedia says the PSI of .30-06 is 58k for CIP and 60k for SAAMI. I keep seeing people say it's ~50k, so what's up with that?

 

[MiG25]

I'm no reloader, but wikipedia says the PSI of .30-06 is 58k for CIP and 60k for SAAMI. I keep seeing people say it's ~50k, so what's up with that?

They say PSI, but it is probably CUP (copper unit of pressure). Regardless, they had loads of higher pressure for the 6.5 than the 30-06 and the 7.65 Argentine was higher still.

 

[tokguy]

They say PSI, but it is probably CUP (copper unit of pressure). Regardless, they had loads of higher pressure for the 6.5 than the 30-06 and the 7.65 Argentine was higher still.

That is a tad spooky that the 7.65 runs that pressure. Got a real handy 1891 carbine ( bubba, but nice still), but I'm guessing it's not famous for its strength like a 98...

 

[p.Rundle]

They say PSI, but it is probably CUP (copper unit of pressure). Regardless, they had loads of higher pressure for the 6.5 than the 30-06 and the 7.65 Argentine was higher still.

That is a tad spooky that the 7.65 runs that pressure. Got a real handy 1891 carbine ( bubba, but nice still), but I'm guessing it's not famous for its strength like a 98...

Truly that gives me clench butthole lol. Very scary for me. I've always avoided super-high pressure cartridges because I don't like the idea of an uncontainable kaboom.

 

[bearhunter]

In Jerry Kuhnhausen's book on the Mauser, he expresses concern about 98s being converted to .375H&H because of what happens to the receiver behind the lower locking abutment.
Keep in mind that PH, Zastava, and others made .375s in standard length 98 actions.
If one of these rifles - like those being sold by TradeEx - was made up commercially in Sweden, I wouldn't worry about a 96 in .30-06 or 8x57.
In the event of a case failure, a 98's gas handling is superior to the earlier Mausers, and to many current production sporting rifles. A 98 does have safety breeching, not quite up to the standard of the Remington 700, but still excellent.
I don't think I would pick a vintage '96 actioned sporter if I was going to hotrod handloaded rounds, use with commercial equivalent loads one should be just fine.

I have an M38 action that was rebarreled and chambered to 6mm Remington. It's reached the point where it needs another barrel replacement. I also converted it to #### on opening with a kit, purchased from Sheridan.

Never a sign of stretching or set back.

I recently maganfluxed the receiver to check for cracks or stress indications. Still looks as good as when the conversion was done over twenty years ago.

As for the pressures in my last post, they were listed as Pounds per Square Inch, not Copper Units of Pressure. If they were, I would have printed CUP.

My 38 was tested with high pressure cartridges, developing around 65,000 psi, while tied to a wheel. Three times. I did this before I put it beside my face to shoot.

The action is strong enough for factory loaded ammunition and hand loads IMHO.

If the old M91 Mausers digested 7.65x53 ammunition, commercial and milspec the 93/95/96 rifles were supposed to be stronger, so should be fine, within their tolerances

Hot rodding any action is a dubious practice.

 

[MiG25]

That is a tad spooky that the 7.65 runs that pressure. Got a real handy 1891 carbine ( bubba, but nice still), but I'm guessing it's not famous for its strength like a 98...

In "Textbook of Small Arms 1909" the highest pressure load is the 7x57 Spanish Mauser at 22.3 tons per sq in, this is pushing 50,000 psi.

Highest pressures listed:

1. 7mm Spanish Mauser
2. German Patrone 88
3. Greek 6.5x54
4. 30-06
5. 7.65x54 and 8x50R Austrian

It is interesting that 4 of 5 are today considered to be for weak actions, the Spanish Mausers especially.

Personally I wouldn't worry about a Swede conversion to 30-06, the Swedes aren't known for making booby traps.

 

[rifleman762]

I had a reloading "whoops" that demonstrates (to me) the strength and gas-handling of the Swedish M96 action. I hadn't checked the brass length on my once-fired 6.5x55 brass and had a round that managed to pinch the bullet and spike the pressure. I remember having a hard push to close the bolt handle and figured it was just a case that didn't push the shoulder back as far as the rest...

I fired the round and all seemed fine. Until I tried to open the bolt! Had to hammer it open, couldn't get it with my bare hands. When the brass came out, the case head was expanded so much that it looked like a mini belted magnum! There was a visible notch where it had expanded against the edge of the chamber. Primer fell out, obviously.

I shot that rifle for many more years after that.

Just one man's experience, take it for what it's worth.

 

[Eaglelord17]

I'm no reloader, but wikipedia says the PSI of .30-06 is 58k for CIP and 60k for SAAMI. I keep seeing people say it's ~50k, so what's up with that?

Depends on your loading. Original M2 ball ammo is about the same pressure as 7.62 NATO but modern .30-06 hunting rounds are more powerful.