I use the lyman devastator and 16 grains of 2400 in my 4" 44 mag for a self defense load. It is mild enough that i can get mulitiple shots, and usually holsd together shooting into water. Even at the fairly low vewlocity(1100 fps) is is a real winner. sand doesn't even make it comletely seperate the nose form the body. I think it would be ans excewllent load for a carbine tt the velocity you spoke of. Mine are eadly accurate, too. My load should do more than you ant in a rifle. as for alloy, I have use d water dropped whell weights, but I have switched to just air colling themn. Range scrap, mostly from 22 long rifle make a prettier bllet with less nose problems. They saeem tougher, too.