The first bca 243 I tried I used some of my hand loads I loaded long for my 700 VLS custom. I stuck one in the chamber and the bolt seized in place. I had to remove the upper and then creatively tap out the round. I measured my chamber and I was about a 1/4" longer than max OAL. I hand loaded .04" shorter than max AOL and never stuck once since in either of my 243 BCA uppers. You might have had a round loaded to long or the bullet backed out of the case during recoil. Besides the 90 grain FMJ seirras I jammed in my gun I've only tried 55 grain Noslers and 60 grain seirra HPs loaded over 4k. Both will shoot .3's with both bullets. I'll have to try some heavier projectiles some day. Never used either after my ladder testing. I also have CMC 2.5 pound single stage triggers in them. I wanted a 22-250 BCA but it would probably sit around like my 243’s. I'd rather use a lighter bolt gun when calling.