Primer Movement

[beerbelly]

While checking for length on my fired .303 BRITISH brass, I found that the primers have backed out about .005. Is this normal or do I have a problem?
                           Beerbelly

[Lone Star]

This is an indication of low pressures and the expected excess headspace of the SMLE rifles.  Since the primes protrude so little I'd not worry about it.  If you want to "fix" it then your only recourse is to get a new bolt head to correct the headspace - this is how the armory did it and bolt heads are made with different dimensions to correct this exact problem.  But in your case it is not an issue - 0.005" is acceptable.  Heat the loads up a bit and the primers won't protrude any more - but that isn't the right solution IMO.  If it isn't broken, don't fix it.



.

[beerbelly]

Thanks for the info I am still new at this and trying to be careful.
                       Beerbelly

[wncchester]

Primers can only back out if there is excess headspace.  That need be of little concern to a handloader.  Just don't "full" length resize the cases, leave them a bit longer than the die to shell holder allows so they can better fit the chamber. 

Slight excess headspace in a military rifle is not a bad thing, it allows the cartridges to chamber freely even if they are a bit dirty or rusty.  The cases were not expected to be reused so it didn't matter to them.  Not so with reloaders!

[Tom W.]

Too light of a load will cause primers to back out, too....It happened to me with my 30-06 and some light loads of IMR3031. My standard loads work just fine.


Try putting and otherwise empty case into a revolver with a live primer and popping it off.....