geez 1.5 MOA for American Eagle. I forgot about that. Nice.
This was how it was set up that day I shot these above. (2x7 leupy, springy gen III mount used as a single point, cheap weaver rings,i wait correction, those are leupy rings I think) The first pic in the previous post was with a 3x9 and the rear screw installed. I took the rear screw out because I swear my zero was wandering at times and I feel like using it as a single point mount solved that problem. I am not impressed with it at all. I could blame the mount for not getting better groups than I have, but I figure it's also me. I usually shoot prone off of a bag. I did that day at 200 yards. They're not terrible though and probably what an average guy could do with a loaded. I loved how consistent portugese ammo is. It's sweet.
As far as cutting groups in half. Ammo always makes a difference. How much, just depends. Handloading and tailoring handloads to the gun is really the way to go for really good accuracy. From what I can tell. I never made that leap myself though.