I have the chance to purchase a 20" version AR-10T. I have always wanted to do a Semi precision gun but couldn't afford a GAP or POF. What can I expect accuracy wise from a 20" AR-10T? I'm a better than average shooter but not a professional. I can shoot the majority of guns to their potential, MOST(everybody has their bad days) of the time. Also, what is the twist on the armalites? I think it is a 1-10 but just want to be sure. If it does not shoot to my liking how does GA or other places get thier rifles to shoot 1/2moa or better? Do they accurize the bolt/carrier (Don't even know if it's possible) similar to how they accurize a 700 action or is it all in the barrel of choice for a AR10 style rifle?