doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com How many Times has it been Proofed?

I have a Stephen Grant 12ga SLE with so many proofs that I can't determine how many times it has been proof tested. I see 3-1/4 tons, 732 and .736 bore dimensions and then sleeved and 850 BAR and 2-3/4" and 70mm. In its current sleeved state the barrels are .722 all over and .700 chokes. How many proofs has it been subjected to? Here are photos: https://imgur.com/gallery/qvSXPwW

All of them

The important one is the latest one. Sorry, I don't have all the London proof mark references., I know somebody does here, though.

The original Birmingham proof was 1983 (J & partial B in the circle) at 3 1/4 TONS
After sleeving the London Proof is 1999 at CIP standard proof; Maximum Average (SERVICE) Pressure 740 BAR = 10,733 psi; Maximum Statistical Individual Pressure 850 BAR = 12,328 psi
The original bore was 12 = .729 to .739". The sleeved bore is .736"

Now I am confused. According to Louis at AG & L, this gun was built in 1907. If these barrels were proofed in 1983 and again in 1999, the barrels are not original to the gun. If the barrels at one time measured .732 and .736, how can they now measure a perfect .722 from chamber to choke, with .700 chokes?

Drew;

I call your attention to the Crown over V and the 12 over C inside of the diamond both of the 1925-1954 and earlier era.

Vol;

It is difficult to see the lines of the lumps on these barrels to determine if the lumps are chopper lumps or if they are dovetail. Remove the extractors and see if the lines through the lumps can be seen then they are chopper lump--these barrels may be original to the gun as the Crown/V and 12/C inside of a diamond was used in 1907.

One expects a 1907 Grant to have chopper lump barrels

bushveld is correct. That is likely the original string of markings.
In addition, beneath the SLEEVED on both flats is the Crown over R reproof mark and possibly 1 1/8 oz.

Vol;

Further to the confusion of the bore diameter of the sleeved tube section, look out on the tubes between the flats and the fore end loop to see if the bore diameters are marked on the tubes--either in inches or millimeters.

I'll correct myself again. The .736" and .732" would have been at the time of the 1983 proof. In 99' the bore would have been marked in mm.