Thread: Point of impact shifts between serials?

Ammunition with temperature change - this I would have thought would more likely show a more continuous change in POI. What you have described is two well defined vertical impact positions. This would indicate to me the rifle and associated equipment - or the shooting setup - moving between one of two states.

If you are prepared to swear to the consistency of your shooting & setup throughout the six groups to be able to remove that from the possibilities, then one of the usual culprits is probably the cause: movement in the bases or rings, internal movement of the scope reticle, unintentional but well defined differences in the ammo, (different loads, bullets, seating etc.), bedding - moving between two different metalwork-to-stock positions.