Another question. My rifle looks to be microgrooved. I have read that some 44 ammo can tumble out of the barrel. What has worked best in your rifles?
Oh, they will not. The only bullet that might tumble would be a short (light) full wadcutter bullet being shot at 50 yards or more. That is because of the bullet design though and has nothing to do with the microgroove rifling. My experience with microgroove barrels is that they will shoot lead fine if they are sized fat. I've driven .311's in a 336CS 30/30 to a tad over 1700 with no leading, microgroove rifling.