Greetings,
I got a 444 Marlin GG a few years back. I worked up a 240 grain load using H-335 and regular primers. After a lot of unburned powder was left in the barrel, I switch to magnum (Fed 215) primers, and worked up the pressure loads again. Works great - lots of bang / recoil and no unburned powder in the barrel!
A couple months ago I got a friend to part with his 45-70 GG. I started out with 250 grain Barnes X-bullets. I jumped straight to the magnum primers and carefully worked up loads using IMR-4895 powder. I'm at a max load now and I've got (1) unburned powder in the barrel, (2) significantly less recoil than the 444 Marlin, and (3) 1900 fps velocities. I've gone back and put as much crimp onto the case as I can stand and there's no real improvement.
Any advice, before I give up and go to 300 grain Barnes bullets?
Thanks in advance for any replies,
B. Noz.