My 2 pennies worth, I stopped using trailboss, bullseye, or any of these fast pistol powder in antique handguns. The pressure curve on these is much more abrupt than 3f black.
I use unique for most of my antique revolvers now. It's close to 3f burn speed.
I've heard some of the BPCR guys will use 2400, 5744, 4198 and those kinds of slower powders for 38-40's, 44-40's, and 45-70's in original black powder era guns, since apparently 2400 is slower than 2F burn rate. Have you ever tried those slower powders in a pistol cartridge?


















































