US manufacturers were afraid some dimwit would try and shoot a full power .323 through their .318 bore Gewehr 88 and blow up the gun, and hurt themselves. Europeans figured if you don't know what ammo your gun can safely shoot, you are a moron and deserve whatever happens to you
It turns out the Germans were also very worried about 323 bullets down the bore of their M88 rifles. They were having barrel blowups in 318 barrels with period ammunition, even after increasing the free bore. The primary cause was poor barrel steel. No one intended to make poor quality barrel steel, it was just the technology of the period was so primitive that the steels of the day were very inconstant and low quality.
I don't think SAAMI standards are unrealistic for period actions. While I have not found an explicit statement to the design loads that Paul Mauser used, you can infer what the actions were designed to hold. There is information about the proof pressures used in M98 actions.
Rifle Magazine Issue 159 May 1995 Dear Editor pg 10
http://www.riflemagazine.com/magazine/PDF/ri159partial.pdf
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
Page 103. 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.
The lugs broke on 1:1000 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. “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.
The article indicates it was applied to the 1898. The 1939 German proof law called for proof at 130% of service load pressure. The maximum working pressure of the German 7.9 sS cartridge was 47kpsi (per forum posters), so presumably the proof pressure for a late Model 1898 would exceed that by the normal 30%, or 61k psi.
Unless someone can produce credible data as to the proof standards of later 98 actions, and the design limits used by Paul Mauser, I am going to state that it is reasonable that the action was designed to support cartridges of 43, 371 psia with a case head diameter of 0.470”. I believe that a pressure standard for these rifles of 43, 371 lbs/ in ² is reasonable based on the SAAMI spec pressure of 35, 000 lbs/ in ². Obviously SAAMI researched this issue, probably determined original pressure standards, then used wise judgment about the age, uncertain previous history, unknown storage, usage, the known limited strength of period plain carbon steel actions, and as an industry, they were are not willing to accept the liability involved with selling new ammunition of a higher pressure.
Later actions, and I consider the actions made in the 1930's to generally fall in that category, the steel was better so pressures could be bumped up a bit, but it is folly to chamber a military Mauser action in a high pressure cartridge or worse, as a belted magnum.
