Well my 30-338 was built on a post 64 action and has med heavy sporter barrel that is 28" long and velocity wise out preforms both my 300 Win Mags as well as my 308 Norma. The barrel is long but cheap velocity, it was also throated to seat a 180 gr BT at the base of the neck so as not to intrude in the powder capacity. OAL is around 3.56" and muzzle velocity at 3150 fps with IMR 4831 and IMR 4350 loads. It wears a MK4 LR leupold with 300 Mag 180 gr dial on it which doesn't match the actual flatness of the trajectory as good as it could. Something I need to fix with a new dial I suppose. Damned accurate. The older Sierra manuals had data on these. MB
