Not sure about .338 barrels on twist never owned one. I'd check the twist of the rifle vs the weight of the bullets your shooting. I've seen this first hand where a rifle spread bullets all over a target to putting them in the same hole by changing the weight of the bullet. I'm thinking bigbulls is right on checking those things out too.

We have the best gunsmith in NM to take a look at it this comming week. Do you guys think the chamber was reamed out of round, or the muzzle break's crown not perfect since it is one solid piece of the barrel? Could the chamber be so polished it can not grip the case? Thanks folks!!

It is certainly a possibility.

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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