I have one white that seems to have a bigger diameter barrel than the others,I use harvester red crushed ribbed sabot in it.It really tighten up my groups.If you happen to have a 54.I would try mmp purple sabot and a 50 cal bullet,one that's shoots fine for me is speer 50 cal,325 grain hollowpoint.I have never recovered one,so I cant say about the expansion,but I have taken several deer with this bullet and its deadly.