303 Brass Head separation question

Brassman66

Brassman66

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I been reloading Rifle & Handgun Cartridges for almost 50 years and still learning new stuff. Recently I run into a problem where I have not found an answer for so far. By checking (looking for the telltale ring and also Wire scratch method) some of the .303 British Brass which I was told is once fired seem to be on the verge of Head separation.

Is it possible that some Brands of .303 British Shells get to almost head separation condition by being fired ONLY ONCE ?

I reloaded many hundreds of .303 British cases before, probably averaging 4 to 6 times before Head separation signs showed up.

Thanks in advance for your comment & advice.

Cheers
 
Depending on the rifle and the ammunition, incipient separations can happen on the first firing. I have sorted a good sized batch of IVI ammunition fired in issue rifles, and up to 20% must be culled.
If the cases have thinner than usual rims, the risk of separations increases.
 
Some rifles have looser chambers then others
This directly affects the condition of the brass, even once fired brass
The #4 Enfield I sold had a really good chamber in it I got 6 plus loadings on the cases
I’ve heard of rifles blowing up brass after 2 or three loadings
 
Thanks for your reply's. I guess anything is possible but there are several .303 Military Rifles I reload for, every one of them I am able to reload for at least 4 times before I have to chuck them for safety reasons.

The Brass in question is Winchester, RP and Federal.
So it seems the only logical explanation would be then, the Brass in question was fired in a Rifle with questionable Chamber tolerances.

Cheers
 
The once fired factory loaded Winchester .303 British case below stretched and thinned .009 on its first firing. The rifles headspace was just a smidgen under .067 and I was told to stay away and not use Winchester brass in any 303 British rifle.

YoV80b4.jpg


And a Enfield rifle at the max military headspace of .074 and a rim thickness of .058 will have .016 head clearance. And you normally only want to bump the case shoulder back .001 or .002 on most modern bolt actions for .001 to .002 head clearance.

sHgqVJR.gif


HK76WCp.jpg


In my opinion, Prvi Partizan .303 British brass is one of the best cases for reloading, it has a larger base diameter, it is .010 thicker in the base and has thicker rims.

The Winchester case below started to seperate on its second firing after being full length resized.

DVy4C4T.jpg
 
Last edited:
bigedp51 said:
The once fired factory loaded Winchester .303 British case below stretched and thinned .009 on its first firing. The rifles headspace was just a smidgen under .067 and I was told to stay away and not use Winchester brass in any 303 British rifle.

And a Enfield rifle at the max military headspace of .074 and a rim thickness of .058 will have .016 head clearance. And you normally only want to bump the case shoulder back .001 or .002 on most modern bolt actions for .001 to .002 head clearance.

sHgqVJR.gif


HK76WCp.jpg


In my opinion, Prvi Partizan .303 British brass is one of the best cases for reloading, it has a larger base diameter, it is .010 thicker in the base and has thicker rims.

The Winchester case below started to seperate on its second firing after being full length resized.

DVy4C4T.jpg
Click to expand...

Thank you posting the Diagrams, ideal for explaining !

Cheers
 
There are rifles out there with excess headspace. Rifles assembled by untrained workers out of parts bins and rifles worn to the point they'll swallow a no go guage are out there. I've definitely heard of a few LE's that would have case head separations on the first firing. Luckily with interchangeable bolt heads in 4 lengths and spare bolts all over its usually fixable with a,set of headspace guages and some trial and error.
 
Headspace on a Lee Enfield is about the clearance for the rim of the case. Nothing to do with length or shape of the chamber. The whole point of bigedp41's post is to make the brass fit the chamber body - on the first firing - essentially, then headspacing off the chamber shoulder, not off the case rim. Always going to have plus/minus on headspace on the rim- therefore always going to have case stretch, if cases Full Length Sized after firing. Not the same as a bottleneck rimless, like a 30-06!!
 
Be sure to look up the "O-Ring Technique" - many reloaders fire cartridges with O-Rings attached to control the headspace and reduce stretching that leads to case head separation.

Also worth investigating whether the correct bolt head has been installed, as others have mentioned.
 
trkyhunter said:
try just neck sizing and keep the cases organized to go back into the same rifle
Click to expand...

That's what I've been doing for 20 years with over sized military chambers, not one head seperation yet.
There is a bit if an "anti neck sizing" mentality on this forum and I never understood why....
 
You can place a thin rubber o-ring around the rim to hold the case against the bolt face to fire form the case.

leGysA2.jpg


And by neck sizing only the cases will headspace off the shoulder and held next to the bolt face.

AQEQ9Vw.jpg


Below using Hornady 100 grain .312 pistol bullets, reduced loads and a rubber o-ring for fire forming cases.

HHDfGl9.jpg


FCHGvIZ.jpg
 
I only neck size but I had case head separation after one reloading before. Since then I have shot many without issue so go figure. I didn't know people full length resize 303 much but I can see that causing issues.
 
I've has particular issues with Winchester blue bag brass. It seems particularly brittle - neck splits on first firing in a tight chambered P-14. I've annealed the rest, but question its longevity at the web.
 
I don't have the patience for putting an o-ring on my ammunition. Neck sizing is more than sufficient but I only have one LE and it has a fairly tight chamber.
 
I can see two different re-loading process for 303 British being discussed? One guy buys factory ammo, shoots it at deer or moose, collects empty brass and eventually wants to reload it. Sometimes even collects empty fired brass from other rifles. Another guy buys bags of bulk brass - fire forms it to fit his chamber (often using o-ring trick or similar), then reloads it to go hunting with - may or may not collect the fired cases for reloading. First guy more likely to have the head separations within a couple re-loads - his first shot likely started the incipient head separation / case wall stretch - can not undo that, once it has occurred. Neck sizing only, might gain a couple more loads, but only if brass segregated for each rifle, and only so long as reloaded round can still be chambered - eventually shoulder will need to be "pushed back". No way that I can think of to transfer the "head spacing" from the rim to the case shoulder, without fire-forming that case at least once.
 
Reading all the comments reminds me of the same story I am having with .250 Savage. Yes ,,,, diffent rifles have had different
chamber sizes , used neck sizer , still have had many necks seperate after 2nd. shot. Trouble hear is that .250 brass is hard & exspensive to
get.
 
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