My Hawken would invariably shoot the first shot from a clean barrel a couple of inches higher than subsequent shots. And as it got real fouled and the bullets got harder to seat, it would shoot even lower yet. Knowing this tendency, I would sight in for that first shot and carry the gun clean in the field. 3" high at 100 yards for the first shot and right on at 100 yards for the second shot.

My T/C inlines are all printing the same from first shot to last shot. I swab between shots, so each load is passing through a relatively clean barrel. They are also very good about holding zero over time, and not changing point of impact after removing the stock for a thorough cleaning.