Carbon build up at throat and up. regular cleaning normally does not get carbon out.I have a 6.5 CM have no idea of how many rounds Ive put through it....................i would guess well over 1500 The issue Im having is that shooting the 143 ELD-X Ive alway shot at 1/2 MOA at 200 yards Now im having a hard time keeping my groups under 2 inches at 100 Same load ive always shot. This morning cool weather dead calm I shot three 5 shot groups and both were over 3" at 100 Crazy..............Im guessing my barrel has had it .
I even tried brand new Lapua Brass I anneal after each shot
It that a fair assumption?