OK I shoot a Encore in 308. I have shot some pretty stout loads in it plus factory loads and I have never noticed a shift of impact. I never heard of this issue until I saw an ad above the forum that sells locking pins for the Encore that locks the pin in place so it does not shift and supposedly change impact. So is this a valid concern or just a chance to sell a gimmick to guys who read the ad and figure they need the pin. At 40 bucks it is not a cheap pin and I always figure if it is not broke don't fix it. I have not had a problem have others here? Like I said is this a valid issue or a gimmick to sell a replacement part?