It shoots .75 to 1 inch groups. No problem with the rifle. I was just wondering why you never hear of gunsmith customizing a BAR.
I'm not a gunsmith but I will throw out a couple of guesses. First, they shoot well enough from the factory for what they are....hunting rifles. I wish I could outshoot mine but that won't be happening anytime soon. So, the demand for "accurizing" one probably is not there.
My understanding is that handloading is somewhat limited with semi-autos. You can't fool around with OAL and powders like you can with bolt guns....you basically have to duplicate factory ammo. The tolerences in the chambers have to be more loose than a bolt gun to ensure proper functioning.
Rebarreling is pretty much out because of the gas ports and housing for the piston that are on the barrel. Ditto things like refacing and squaring the bolt. Trigger work could be dicey....a little creep on a semi auto might be a good thing. It has a two piece stock with a moving piston under the forearm....so I guess the bedding tricks people use on bolt guns are not going to happen.