A smoking trail of guns and Jeeps behind you... grins...
Hey, can't remember if we talked about this.
The non-geometric way your groups grow as the range increases is still baffling to me. Now granted, baffling me ain't rocket science, but.... have you tried a different scope on there? Could the scope have a major parallax issue?
Otherwise, for the life of me I can't think of how your groups could grow like that other than a really wacky stability thing that seems unlikely.
I'm sure I'm just being daft here... no public floggings please....