The R1 has a lot of potential for accuracy. The key was finding a scope and mount that could stand up to the recoil of that particular semi auto.( I’m sure others apply)The bolt cycling and smacking the heel of the upper receiver would throw a lesser scope off zero very easily. I suspect this is why the accuracy reputation is so hit and miss with this particular gun.
Consistently under an inch with hand loaded ammunition with a good mounting system and tough scope ( sightron ) Couldn’t comment on factory ammo.
