Trim Length


Well-Known Member
Dec 12, 2005
Tucson Az
Find out where your chamber ends with these:

I discovered years ago that many chambers won't require you to trim the brass for many firings/ sizings. Some factory chambers are as much as .070" longer than the recommended trim length listed in the loading books. Why trim if you don't have to?

You will have to remove much of the neck of a case for use with the gauge. Seat the gauge long in the case then close bolt on it. The plug will slide rearwards. Carefully remove and measure the OAL to determine end of chamber dimension. I like to repeat this several times to be certain.

If you have access to a lathe you can get specs on the gauge on Varmint Al's site so you can make your own. I used aluminum or brass:

Varmint Al's Mini Lathe Page

Al also explains about its useage:

Varmint Al's Handloading/Reloading Page