Quote Originally Posted by Shooter71462 View Post
I swapped the barrel from a stock 22-250 to a 243 Win. Went with the a new Shillen 26" varmint. According to the "Go" and "No Go" gauges spacing is right. Then I tried to chamber several pcs of brass and none would chamber. Always stick and some would not allow the bolt to go down. These were all full sized and primed. I checked them and they are within tolerance. Any ideas?
A chamber should be .005 larger than than commercial ammo(ideally), the no-go gage is +0.005 over a go-gage and the field-gage is 0.009 over the go-gage, this would give commercial ammo .014 head space when fired in a chamber that a field-gage fit in.


GO: Corresponds to the minimum chamber dimensions. If a rifle closes on a GO gage, the chamber will accept ammunition that is made to SAAMI’s maximum specifications. The GO gage is essential for checking a newly-reamed chamber in order to ensure a tight, accurate and safe chamber that will accept SAAMI maximum ammo. Although the GO gage is necessary for a gunsmith or armorer, it usually has fewer applications for the collector or surplus firearms purchaser.
NO-GO: Corresponds to the maximum headspace recommended for gunsmiths chambering new firearms. This is NOT a SAAMI-maximum measurement. If a rifle closes on a NO-GO gage, it may still be within SAAMI specifications or it may have excessive headspace. To determine if there is excessive headspace, the chamber should then be checked with a FIELD gage. The NO-GO gage is essential for checking a newly-reamed chamber in order to ensure a tight and accurate chamber.
FIELD: Corresponds to the longest safe headspace. If a rifle closes on a FIELD gage, its chamber is dangerously close to, or longer than, SAAMI’s specified maximum chamber size. If chamber headspace is excessive, the gun should be taken out of service until it has been inspected and repaired by a competent gunsmith. FIELD gages are slightly shorter than the SAAMI maximum in order to give a small safety margin

Hope this helps