The British eventually approved a lighter proof for 2" 12's. I believe that was about the same time that they changed from the 1925 proof rules to the 1954 proof rules. (The "tons" rules.) Found the reference. Here it is, from Vic Venters' book "Gun Craft", from former Birmingham proofmaster Roger Lees: "In general, it may be said that under the new rules of proof (reference to 1954 rules) no arm will receive a more severe proof than hitherto. Some, such as the 12 bore 2 inch and 4 and 8 bore guns, will now receive a less severe proof than they received heretofore."
More recently, when Arrieta made some 2" 12's, those guns were given a heavier proof than British 2" 12s. The guns themselves were also heavier, weighing as much as some light British 2 1/2" 12's.
| 