I have a factory Remington 700 chambered for 300 wby. 24" 10 twist looks goo, bought used no history. Friend had one that shot very well so I got one. worked on loads and all were fair to good .75 - 1.5 at 100 yards. then I went to 212 Hornady ELDX with 80gr. 7828 and got it to shoot .5 or better except for a flyer in any direction about 1to 11/2 in off. why with once fired brass, cci 250 neck sized only. free floated in plastic or syn. stock.