98 receiver metallurgy

[EO1]

Although I'm new here now, I was previously a member a few years back but forgot all of my login info.

Here is what I have.....a NOS, never had a barrel screwed on, 98 receiver dated 1935 with the BUGN proof marks which I presume is Oberndorf made even though it is not stamped as such.
After doing a search here, there is a consensus that WW1 and prior made receivers are softer carbon steel. I know that it will be fine with 8x57 but would it be ok with being built into a 270 or would it be too soft or need a heat treat ? Pardon my ignorance on this subject as I am a bit ignorant on the metallurgy timeline on these.

 

[troy fairweather]

welcome back. we need pics lol. 35 should be fine for the 270. tho if i had that virgin action i would send it out to be tested. worth the money if the action is a virgin 98. i shall ask you to consider a traditional mauser cartridge and not a 270 win. the 6.5 swede 6.5x57. 7x57 7x64 brenneke. 9.3x62 there are some others as well. very much recommend the 7mms all o these you can get cheap ppu hunting ammo from $12 to $20 for 20. what would the rifle be used for.

 

[EO1]

I'm out of town just now and cant do pics. When you say "tested", I presume you are referring to a hardness test ? Privi is good ammo at a decent price. I've already have a half dozen 7x57s and some 6.5x55s. The 270 barrel is a new Zastava made one that I've had for several years.
Intended purpose ? Probably just something else my heirs are going to fight over.

 

[boom boom]

Max pressure for .270 Winchester 65k psi SAAMI, 8x57 Mauser 56,250 psi from CIP (SAAMI's is 35k psi due to GEW 88's out there with .318 barrels). Issue ammo for the Germans in WWII was about 50k psi (not the hot machine gun stuff).

Does yours have the Mauser banner and the words Standard Modell on the receiver? If so, you might find this article useful https://www.americanrifleman.org/ar...d-gun-mauser-98-standard-modell-banner-rifle/

M98's are case hardened carbon steel so a non-destructive test will mainly tell you how tough the exterior is--the inside of the m98 or all military mausers is softer--so like a hammer, the softer core under the hardened surface can deform under some measure of excess pressure which is a passive safety from overload events. A destructive test will tell you what you need to know but at the expense of the receiver.

But, repeated doses of high pressure will cause the receiver's bolt lug recess engagement surfaces to deform--leading to progressively more difficult operation, increased headspace, etc. Some, depending on the model of 98, have reported even stretching of the receiver itself allegedly because of the C-ring relief cut in military Mausers. Others have separated at the thumb cut area for stripper clip loadings which weakens the left receiver wall quite a bit.

For that reason, some prefer to re-heat treat the receiver to ensure safety and durability when using modern high pressure rounds. This is a risk that re-heat treatment can warp the receiver so it is best to send it to a firm that specializes in it. Others do not do this and report everything is just fine which it might be if you do not hot rod your loads and keep them down to the bottom end of the range. A few, who grew up in the age of plentiful milsurps, treated the receivers as essentially disposable as most hunting rifles do not see high round counts so one that last 400-500 rounds would be literally a lifetime's worth of rounds for some hunting rifles. A few then requalify the barrel and shoot a few more (but if the receiver is stretched or the lug engagement surfaces are buggered then it is only a short term fix.

Your call.

 

[EO1]

Yes, I'm aware of the pressures just not well versed on mid 30s metallurgy vs earlier. No Mauser banner.
It will be going to Pacmet then.

 

[boom boom]

Yes, I'm aware of the pressures just not well versed on mid 30s metallurgy vs earlier. No Mauser banner.
It will be going to Pacmet then.

It is carbon steel, the 1930's through early war Mausers demonstrate high quality heat treatment for the designed cartridge. Oberndorf Mausers were made consistently by people who knew how to make them. That being said, it would be like firing a +p round in a firearm designed for regular pressure. Not that it would blow up instantly but wear would be increased by an unpredictable margin.

 

[EO1]

That's a good analogy.