RE: Burris Fullfield 2 scope
Sounds like the scope ok to me, if not you wouldn't be achieving any groups. You said at 50 it was cutting near the same hole, on sunday a friends gun wouldn't do that, so after checking the mountswe changed the scope, re-bore sighted and it started grouping. Scope gone bad for sure.
I'd say look at the rest/shooterand ammo. Try using sand bags to see if that shores things up, don't over grip, make sure your not pressing down on the barrel or rest points aren't under the barreland squeeze not jerk the trigger. Could have a buddy shoot it for comparison sake. Try different ammo. You never said how fast you were shooting but I'd try 3 shot groups and then let the barrel come back to ambient temp before firing the next group to rule out heat.Check the action screws and any possiblebedding issues.Does the gun group off a cold barrel to the same general POI before drifting?
Also don't touch the adjustment caps if your on the paper, first achieve a baseline (grouping)then fine tune for POI. Chasing the bull='s wasted ammo and frustration.
Best of luck.