Finally picked up a 300 blk out barrel for my ar, it's 16" 1-9 twist, want to know from you that have been shooting this round for awhile what the heaviest bool it that will stabilize for his twist, bought this just to shoot subsonic, have a encore for supersonic lighter loads.
Have molds from 170-248gr and plenty of heavy J word bullets but want to keep this one all cast.
Also what would be the best hardness so there is no damage to the nose when feeding from magazine?