TXCOONDOG
Well-known member
I have an X-Caliber barrel chambered in .243 (AR 10). I full length resized the Lapua brass and seated the bullet (87gr VMAX) with a light crimp (.003" neck tension). The dummy rounds would not chamber fully. I checked with a bore scope and didn't see any burrs, tooling marks, etc. I colored the case with lip stick so I could see where it was hitting. It was the case neck so I turned the brass down .004" and it chambered fine (pushing the BCG closed by hand).
Should I turn the case neck down an additional .002"-.003" to ensure the case neck opens up fully and releases the bullet consistently or will that make the case necks too thin?
The case neck wall thickness before turning varies between .376"-.380" using a digital micrometer. The cases have to be turned down to .374"-.375"before the BCG will close with no drag.
Should I turn the case neck down an additional .002"-.003" to ensure the case neck opens up fully and releases the bullet consistently or will that make the case necks too thin?
The case neck wall thickness before turning varies between .376"-.380" using a digital micrometer. The cases have to be turned down to .374"-.375"before the BCG will close with no drag.
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