So here's my question, I have a 5r milspec 223, a custom built 6xc built on a remington short action with a 28" 1:8 twist broughton barrel in an xlr chassis, and a custom built 338 lapua with a 28" broughton 1:9.3 twist rate barrel mounted to a badger m2013 action in a krg chassis. To date the first two shoot lights out at 100 and 200 yards simply printing groups load testing have done surprisingly well, the 223 even shoots factory hornady 75gr match ammo extremely well and I'm in the process of trying to duplicate the results with that ammo with reloads. Both the 223 and 6xc shoot less than 1/4 moa at 100 yards and are both usually still less than 1/2" at 200 but for the life of me I can't get my 338 to do anything better than I could if I were throwing bricks. I have checked the torque on everything, scope mounts, rings, action to chassis, and I can't get it to shoot anything better than 2" at 200 yards. I've tried 3 different bullets. 300gr Berger, 300gr smk and 285gr amax, and only h1000 for powder in lapua cases with cci mag primers, I have tried charge weights ranging from 87-92 grains and have gone up one in one grain increments, have only loaded them to my maximum mag length so I can still use the magazine, case prep involved simply cleaning up the case necks, chamfering, and one would think that by now I should have seen much better results. The gun was smithed by Dixie precision and they have a great reputation for producing rifles that are more than capable so therefore I'm lost. Could anyone shine some light on this for me please? I just don't understand why i can't get it to do any better when I know it should unless I'm expecting too much accuracy wise from a caliber of its size.