Headspace frustration

[BrokenWheel]

AR15 fired brass measured with Hornady case gauge to determine fireformed headspace - the measurements come to about 1.465 to 1.466 inches.

Question (I need conformation!)- I've read that you need to reduce fireformed HS length by .003" when resizing. So that would make my goal 1.462 to 1.463; correct? Seems that 1.462 is a bit on the short side.

 

[rsrocket1]

1.462-3 is quite adequate (not too short) if you are sizing for a bolt action rifle.

If you are shooting this in an AR, you really ought to be full length resizing each time unless you are more concerned about all out accuracy and don't care about misfeeds.

 

[918v]

You want about .005" for semi-autos for reliability.

 

[243winxb]

So that would make my goal 1.462 to 1.463; correct?

I would guess yes, if you have a minimun chamber. Gages dont always give a correct reading. Brass can get shorter on firing if not a maximum loading. http://www.saami.org/PubResources/CC_Drawings/Rifle/223%20Remington.pdf