CZ 457 LPR Match Chamber.

[Meroh]

So since CZ barrels all comply with the mandatory CIP standards, all their chambers are "match grade" as defined by the voluntary US SAMMI "match" standards. When I put a brand new take off 457 Varmint barrel on my 455 action in an oryx I had trouble closing the bolt on TAC22 and CCI STD. I ended up shimming the barrel out 0.0015 (now it closes just slightly harder with ammo that if dry cycling), that is about perfect.

It shoots both well, but Tac-22 markedly better. Hates Eley sport, match and contact. I have some SK Match to try but have not gotten to the range with it. Others like it, so I have great expectations.

So, I have now made two range trips with the SK Standard Plus, not Match. At first glance, shooting the .22 100 yard challenge targets it does not look a whole lot different than than the Tac-22; however when you get the calipers out, group size is slightly smaller. Enough to Justify paying twice as much to tighten up "average" group sizes by .1 or .2". I see just as many fliers.. I don't think I will bother with the SK Std +.