Ok, had my 300wsm all tuned up. 200 grain partitions, Kimber MT, put over 300 rounds through this rig with nary a hiccup. Shoots 1" all day.

I shoot 2 rounds almost touching at 200 yards. Move 1 click left and shoot again.
4" to the left. WTH?
Shoot again at different bullseye. 4" left. WTH?
Move 6 clicks right. Bang, 6" right of bullseye. Shoot again, 6" right. Vertical on all shots is perfect.

Suggestions as to what may have happened?

Thanks