Re: Help, concentricity problems.
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Once you fire the brass one time it takes the basic dimensions of the chamber (hence fireform). Take advantage of the close dimensions and just partial size it so that it gets the compression mentioned earlier when a round is chambered.... You will be pleased with the results.
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Great discussion kraky and Chawlston.
The thing I'm not sure about is the amount of compression you will get between the case-head/bolt-face and the case-shoulder/chamber-shoulder after only one firing. I took the following measurements with a Stoney Point Head and Shoulders Gauge on cases fired from a Steyr 30-06 going from new cases to the 4th firing:
new cases - 4.0400" (the measurement doesn't mean much, just it's relationship to the other measurements)
once fired - 4.0485"
twice fired - 4.0500"
3 times fired - 4.0510"
4 times fired - 4.0515"
These were neck sized with the Lee Collet and after the 4th firing the cases became hard to chamber and had to be PFLR'ed back to 4.0510" to a slight crush fit.
The point is that after the first firing the shoulder was still .003" from a crush fit. I did a test with some loads that were loaded at the same time and found that PFLR'ed loads with the shoulder moved back to a slight crush fit and crimped with the Lee Factory Crimp gave the best results.
Next is to PFLR once fired cases and see if the body sizing moves the shoulder far enough forward (which I can then push back to the proper place) to get a crush fit on once fired brass.
I'm with you Chawlston in that expander buttons are a long ago bad memory. For me it is the Lee Collet Neck Sizer and Redding Body Dies.
When is the best time to turn necks, on new cases or after the first firing?
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