how much clearance after using a chamber ln gauge

jwoolf

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Minuteman
Feb 2, 2010
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Dallas, TX
I'm upping my reloading routine to do way more brass prep than I used to do and, I've ordered a chamber lengh gauge to use along with a digital headspace gauge and a belted magnum collet die.

The question I have here is how much clearance from the case mouth to the end of the chamber do you need to leave to make sure the case mouth doesn't engage the lands when the bullet does?
 
Re: how much clearance after using a chamber ln gauge

If you are 'upping' your reloading routine, trim your brass to SAAMI spec and don't worry about it. I doubt you can grow your brass to the end of your chamber, but it is always better to trim to a specific length for consistency. For a .308, trim to length is 2.005. Max length is 2.015.
 
Re: how much clearance after using a chamber ln gauge

Chamber max length minus .010" for max case length and minus another .010" for min trim length.

example for .223

chamber- 1.772" (1.770")
max trim- 1.762" -.010" (1.760")
Min trim- 1.752" -.010" (1.750")