Full length or neck size (without bumping the shoulder)and shoot 1-2 more times. It will show +....
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How could new, unfired cartridges have a measured headspace that is longer than the fired cases?
Yawn....... ...... ... .Why would you, when you shoot half moa groups at distance from a sling?
C'mon, post the pic. You know you wanna![]()
I have observed new 308 Win and 30-06 primed cases (no powder, bullet) shoulders setting back .002" to .007" when fired. 2 to 3 ounce firing pins striking primers at 9 to 10 fps was the cause.Try this: take a new unfired round. Measure the headspace to the shoulder using the correct comparator. Carefully check that the primer is flush or below flush with the case head. Load it in the mag. Point the gun in a safe direction (may want to do this at the range, depending on your level of comfort/paranoia), hit the bolt release and let the bolt strip the round and chamber it like it would during normal operation. Extract the *unfired* round, and re-measure the headspace.
It is possible for the mass of bolt carrier to shove the shoulder back. It's also possible for a primer sitting 'proud' before firing to get either seated more fully by the firing pin, or just pushed in when everything goes 'bang' and the case head is thrust back against the bolt face under load. It's also possible that if this brass is new/virgin, which assuming factory ammo and not reman it probably is... that the shoulder angle of the virgin case isn't quite the same as the fired case. That can cause some weird variation in readings with your comparator.
As others have said, I'd worry less about comparing the headspace of virgin brass on factory ammo to once fired, than I would about just setting the die so it bumps the shoulder a given amount (3-4 thou) from the fired condition. After *that*, then yeah, pay close attention to the dimension after firing your reloads. The 2x fired headspace should match your 1x fired headspace pretty closely.
Yawn....... ...... ... .
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