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Old 11-14-2012, 8:25 PM
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Calif Mini Calif Mini is offline
Join Date: Jan 2009
Location: Fremont California
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Default Rimfire case rim thickness

Originally Posted by Izzy43 View Post
Great shooting, lot of stress in that last shot. What method do you use to measure rim thickness? SK Std+/Wolf MT is also my ammo of choice, best for the $$$ going in my opinion. Keep shooting with us, new targets every month.
I used a little piece of 12L14 bored out to simulate a chamber. (Actually thought of getting a Bentz chamber reamer to make one) and dropped rounds in and used a dial indicator that measure in tenths of a thousandth of an inch.

Found almost .002" spread in 600 rounds. Grouped first box with the shortest rounds and used these to "foul" the barrel and warmup.

Then marking boxes 2 - 2.4, next 2.5 - 3.0, next 3.1 - 3.5 and finally 3.6 plus.
These numbers were only for reference and have no direct height meaning.


Originally thought I was going to sort by .0002" but there is a lot of variation when sweeping over the rim with a sensitive indicator so went with .0005".

Last edited by Calif Mini; 11-14-2012 at 8:34 PM..
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