Well, after all the money, squabbling, and question asking spent on this scope and particular ARMS equipment, I have a report to give. BTW, thanks to all who have entertained me with their responses!
Optics and mounts: Aimpoint M2, ARMS 39, ARMS M6822
Ammunition: Lake City Lot 4
Gun: Colt 20"
Range: 100 yds
Targets: Clay Birds, 25 meter NRA pistol target
Position: Standing, leaning against tree, no sling.
Credibility: 7th award Marine Corps Rifle Expert rating, Marine Primary Marksmanship Instructor.
1. Aimpoint 4 moa dot, firing at pistol target resulted in MOA group sizes.
2. Aimpoint 4 moa dot: Broke and shattered clay targets all day long.
3. National Match FSP, Aimpoint switched to "off", looking through optics resulted in same MOA group sizes.
4. Aimpoint removed, iron sights only, resulted in same MOA group sizes, but impact 4 inches left.
5. Aimpoint re-mounted to ARMS 39 rail, using red dot, resulted in absolutely no noticeable ZERO change.
Another Marine supported my results almost identically with his groups. BTW, we both went 4 inches left at 100 yards with the Aimpoint optic removed.
Note: This setup could save lives!