Hello,
I've got an early JP Sauer drilling, it is not proofed for smokeless. The shotgun barrels are 16g/2.5in, no problem there. The rifle barrel is somewhat unknown. I see 11.15x65 stamped underneath the barrels in two places. I've determined the bore is 439-440 buy pounding various sized slugs through the bore to see what fits best, 440 seems to fit best and that translates to 10.15mm best fit rather than 11.15. Using a dial-caliber and the 65mm length indicated by the barrel marking I'll buy into that as a reasonable measurement and as such I've trimmed a small lot of 400NE brass to that length. This size brass fits the best in the chamber and fits the extractor perfectly. I fire formed some brass using 440 round ball and a case full of Goex CTG slightly compressed. That worked fine, a little chamber fouling due to the fire-forming exercise, but fine overall. Having some 43 Spanish .439 dia, 370grn bullets on hand I loaded those into the fire-formed brass. Seated to the crimping groove of the bullets, all is well. I actually think I could lengthen the overall cartridge length. The lock up is chopper lump (as near as I can tell) with a small doll's head with side-locks.
My concern is the overall load. All said, with 1/8 of an inch compression of the powder charge in the finished cartridge and the bullet seated, I've got a charge of approximately 80grn of Goex CTG. With that charge of powder and a 370grn bullet, I'm thinking that might be a little on the hot side. I base this assumption on looking at other 40 or so caliber BP cartridges and I'm generally seeing bullets in the range of 200-300grn. But in this cartridge then my powder charge would quickly appoach 100grns compressed.
So, learned forum readers, is the load too hot? Is the bullet weight more important than the charge weight in determining a potential overload? I do not want to pound this gun to pieces after it has survived this long. Here are a couple of pics.
I've got an early JP Sauer drilling, it is not proofed for smokeless. The shotgun barrels are 16g/2.5in, no problem there. The rifle barrel is somewhat unknown. I see 11.15x65 stamped underneath the barrels in two places. I've determined the bore is 439-440 buy pounding various sized slugs through the bore to see what fits best, 440 seems to fit best and that translates to 10.15mm best fit rather than 11.15. Using a dial-caliber and the 65mm length indicated by the barrel marking I'll buy into that as a reasonable measurement and as such I've trimmed a small lot of 400NE brass to that length. This size brass fits the best in the chamber and fits the extractor perfectly. I fire formed some brass using 440 round ball and a case full of Goex CTG slightly compressed. That worked fine, a little chamber fouling due to the fire-forming exercise, but fine overall. Having some 43 Spanish .439 dia, 370grn bullets on hand I loaded those into the fire-formed brass. Seated to the crimping groove of the bullets, all is well. I actually think I could lengthen the overall cartridge length. The lock up is chopper lump (as near as I can tell) with a small doll's head with side-locks.
My concern is the overall load. All said, with 1/8 of an inch compression of the powder charge in the finished cartridge and the bullet seated, I've got a charge of approximately 80grn of Goex CTG. With that charge of powder and a 370grn bullet, I'm thinking that might be a little on the hot side. I base this assumption on looking at other 40 or so caliber BP cartridges and I'm generally seeing bullets in the range of 200-300grn. But in this cartridge then my powder charge would quickly appoach 100grns compressed.
So, learned forum readers, is the load too hot? Is the bullet weight more important than the charge weight in determining a potential overload? I do not want to pound this gun to pieces after it has survived this long. Here are a couple of pics.
