At max headspace in a .303 British Enfield rifle you can have ,017 head clearance. Meaning the case can stretch that much when fired and you "might" get 1 or 2 firings before the case separates.
I would not buy or use any .303 British range pickup brass and only use cases properly fire formed in "MY" chamber. The chambers of WWI Enfield rifles were reamed larger because of poorly made ammunition and the conditions of trench warfare. And these older military No.1 Enfield rifles will stretch the cases badly on the first firing.
Wolfhound- it's yours. Pm me with name & address, when I get enough to warrant postage, I'll send it.
Would a more or less "new" Enfield have the same headspace issues?
I have a Lithgow made Enfield that was made in 1945.
I seriously doubt it had ever been issued. I don't think it left Australia until it was brought into the U.S.
It could have been, but it sure wasn't used much, if at all.
Sorry about the thread jack.
Would a more or less "new" Enfield have the same headspace issues?
I have a Lithgow made Enfield that was made in 1945.
I seriously doubt it had ever been issued. I don't think it left Australia until it was brought into the U.S.
It could have been, but it sure wasn't used much, if at all.
Sorry about the thread jack.
If you look at a SAAMI cartridge and chamber drawings it lists headspace as min and max with a average of .010 between min and max. And the military Enfield rifle headspace is .064 minimum and .074 maximum. And GO and NO-GO gauges have a average of .003 between them and are for setting up new barrels. So this gives you .007 wear until a field gauge and reaching max headspace.
Pacific Tool and Gauge offers three lengths of headspace gauges per rifle caliber. In order from the shortest to longest, they are: GO, NO-GO, and FIELD:
- GO: Corresponds to the minimum chamber dimensions. If a rifle closes on a GO gauge, the chamber will accept ammunition that is made to SAAMI’s maximum specifications. The GO gauge 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 gauge 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 Forster recommends for gunsmiths chambering new, bolt action rifles. This is NOT a SAAMI-maximum measurement. If a rifle closes on a NO-GO gauge, 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 gauge. The NO-GO gauge is a valuable tool 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 gauge, 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 gauges are slightly shorter than the SAAMI maximum in order to give a small safety margin.
The majority of Enfield rifles do not have a headspace problem even at the military maximum of .074. The problem is the majority commercial .303 cases are not made as strong as military cases. Example military 7.62 chambers are larger than .308 chambers and Lake City 7.62 cases are made of harder and thicker brass.
Below on the left is a Prvi Partizan .303 British case that is made to military standards. The Prvi case has thicker rims, is a larger base diameter and is .010 thicker in the base web area. Both cases below were fired in the same No.4 Enfield rifle, so again the Prvi cases are like Lake City 7.62 cases and made heavy duty.
The trick to fire forming your .303 British cases is to use a rubber o-ring or small pony tail rubber bands and slip one around the case. This holds the case against the bolt face and keeps the case from stretching on the first firing.
.303 cases are not made as strong as military cases
After fire forming the cases you neck size only and let the case headspace on its shoulder.
Below fire formed cases using the o-ring method and no case stretching.
When forming cases I use reduced loads and Hornady 100 grain .312 pistol bullets. This make the brass butt plate softer when forming large batches of cases.
The Winchester case on the far right was fired three times and full length resized and started to seperate. And why proper fire forming and neck sizing only will greatly extend case life. And with light loads I have gotten up to 32 reloads before getting split necks.
Below with my RCBS case mastering gauge I can measure case wall thickness and any stretching and thinning of the case.
Once you understand the Enfield rifles long fat chamber, case stretching and proper fire forming your reloads will last a long time.