Do you guys think the chamber was reamed out of round,
It is certainly a possibility.
or the muzzle break's crown not perfect since it is one solid piece of the barrel?
When you say one piece of barrel are you saying that the gunsmith actually reamed out the rifling of the barrel and then drilled holes into the unrifled barrel to create a brake out of the actual barrel?
Or did he thread the end of the Shilen barrel and install a brake that is the same diameter of the barrel creating the look of a single piece of steel?
Shilen only has two twist rates for the .338, a 10 twist and an 8 twist. Either of these will stabilize any hunting bullet you would want to shoot out of the .340.
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