Re: Take off barrels
Factory barrels generally contain stress due to the way they're manufactured (cheap) so expect POI to shift if it gets really hot (rapid firing).
Run Tubbs Final Finish bullets through the factory barrel and then just shoot the hell out of it with minimal cleaning. After a hundred rounds or so Remington factory barrels "settle in" and you can expect sub-moa accuracy from a factory barrel. Clean only when accuracy drops off, and then it takes another 20 or so rounds to get it shooting as it was before.