I have some 12 bore Bismuth Cartridge Co. 3” loads and am wondering if I could use them for ducks with 10-12 silver Gaugemates in a Smallwood 10 bore Damascus hammer gun with 3.5” chambers, superior proofs, and full chokes. Pressure of these shells was reported to be 9500 psi.

The gun presumably started out as 2 7/8" for 1 1/4 oz loads and was rechambered and reproofed before I bought it. The Bismuth are 1 5/8 oz., so probably a bit much for the old wood, but I don't have a lot of them.

Thanks.

I wouldn't...Geo

I ran quite a few of those using Lil Skeeters through an E Grade Lefever with no ill result...Of course it WAS a Lefever...

I believe those boxes were only labeled "Max Dr. Eq."
1 5/8 oz at 1280 fps would be 4 Dr. Eq. and recoil in a 9# gun would be 40 ft/lbs.
1 1/4 oz. 3 1/4 Dr. Eq. (1220 fps) in an 8# gun is 25 ft/lbs

Worked fine in my Scott 10 ga.

I might not be worried about the pressure damaging the barrels so much as cracking the 'ol stock with heavy recoil.

10 gauge guns are as a rule built heavier.