03-03-2018, 06:35 PM
bj139 Wrote:Are you actually measuring this? You are quite a bit off from SAAMI.Those numbers are lifted directly from the datum points shown on the SAAMI chamber drawing for the Grendel.
I see now that I indadvertently used the case drawing for the .308 Win.
The correct data is:
308 win
Near Base 0.4714
Near Shoulder 0.4564
Difference 0.0150
Datum Length 1.2500
Taper 0.0120
My conclusions remain the same.
BTW The Case head and shoulder dimensions are derived from the point of intersections of the lines and cannot be measured. They are for reference only.
The body and shoulder datum dimensions are located at points that can be measured. IIRC these are the points used to validate gages and, in turn, verify that the chamber meets specs.
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"To those who have fought and almost died for it, freedom has a flavor the protected will never know."
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