'Proof is the compulsory and statutory testing of every new shotgun or other small arm before sale to ensure, so far as is practicable, its safety in the hands of the user. Reproof is the similar testing of a small arm which has previously been proved. Both necessarily involve the firing through the barrel of a considerably heavier load than is customary in the sporting field, thereby setting up pressure and stress on the barrel and action much in excess of the pressure generated by standard load cartridges. Such pressure should and is intended to, disclose weakness in guns, whether new or used, for it is preferable that weakness be found at a Proof House rather than in the field, where personal injury may result.'
Quote from the 5th Edition of 'Notes On The Proof Of Shotguns And Other Small Arms' issued by the British Proof Authorities.
Original Black Powder proved guns, most commonly proved over 90 years ago, may not be safe for use with smokeless cartridges and require reproof for nitro powders. ( Further quote, referring to shotguns particularly. It is this which also applies to modern reproductions of muzzle loading pistols designed to fire black powder and which may be insufficiently strong to cope with the pressures of modern nitro powder.) The Ruger is extremely strongly built!
photo of proof mark under barrel of Ruger after reproof Click on the picture for the full sized version. Look at the mess of the stamping of Nitro, but that is what it says! |
nitro proof mark on new cylinder |
Birmingham Proof House
Photos of Birmingham Proof House http://www.virtualbrum.co.uk/heritage/ProofHouse.htm
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