doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 3 inch CIP v 3 inch SAAMI pressures

re: post-1925 and post-1954 proof pressures
“Proof Tests and Proof Marks: Practices of Manufacturers in the United States”, 1934.
Limits are based on the 1925 British Rules of Proof. Long tons are converted to PSI simply by X 2240, and the numbers were measured by LUP so require adding 10 - 14% for modern piezo transducer numbers.



Vic Venters (Jan/Feb 2009 Shooting Sportsman) quoted Roger Lees (Birmingham Proofmaster, both before and after the switch to the 1954 Rules): “The proof loads now set down in [the 1954 Rules] are almost in every instance the proof loading in use under the 1925 rules. In general it may be said that under the new Rules of Proof no arm will receive a more severe proof than hitherto.”