"the concentrcity of the ammunition"
My #1 ammo complaint for factory .223 69g match rounds is overall length. With my Savage I can feel the slight bolt pressure of a long round touching at the last moment of chambering. The lack of bullet jump increases the pressure slightly and will cause a round to strike about 1/2 inch high at 100 yards. This is less common with Black Hills or Federal Premium, but I do notice 2-3 in most every box of PRVI. (but $0.80, $1.10, and $0.50 per round respectively)