It can just be the luck of the draw. Case in point, I wanted a 204 done on the cheap so the barrel came from some unknown source for under $100. It will shoot half inch groups off the bags all day long with my one particular load.
Then I wanted to build an exceptionally accurate 204 so I paid over $350 for a Rainier barrel. It will shoot half inch or smaller groups off the bags with the same load.
I really can't complain about either one of them.
