Case Head Separation Lake City Brass

[mobile7.62]

I was at the range the other day shooting my BCM 16" midlength and experienced my first case head separation with my reloads. I was using TopBrass once fired processed Lake City brass with a moderate charge of Tac and 55 grain soft point on top.I have used this load before with no problems in this rifle and others. In total, this was the second firing of these case's lifetime. Also, I ensured that every case had shoulders bumped down to a proper length via Hornady headspace gauge. Needless-to-say, I was pretty surprised from my experience and started to research. From what I gathered, much 5.56 brass is fired from M249's and it can cause case head separation even after the first reload. Evidently, the combination of a relatively large machine gun chamber and light case walls on 5.56 makes for a greater likelihood of case head separation for reloaders like you and me.

So my question is, is this problem as likely to occur with TopBrass processed LC 7.62x51 brass? I understand most of it will be fired from m240's but I don't know how prevalent this problem may be even with the thicker case walls of 7.62x51 brass. The reason why I ask is because I purchased this Brass for use with my M14SA. As of now, I have used 100 pieces of this brass with my M14SA and they are on their 3rd cycle being reloaded with no problems. Should I be expecting an eventual case head separation to happen?

Thank you

 

[MitchAlsup]

Re: Case Head Separation Lake City Brass

Most of my LC 223/5.56 brass comes from once fired Black Hills Blue Box so by the time I am relaoding it, it has gone through 2 firings. Still, I am getting dozens of reload cycles on them with my regimen.

 

[sinister]

Re: Case Head Separation Lake City Brass

The SAW can be extremely hard on brass:

http://www.dtic.mil/ndia/2011ballistics/11826.pdf

 

[JeffinTX]

Re: Case Head Separation Lake City Brass

Two separate issues: for your LC 5.56 brass, use your Hornady (Stoney Point) gauge and resize to bump the shoulders .003" to ensure easy feed and extraction. More than .005" bump will overwork the brass and lead to premature case separations. I have a lot more brass wear out with split necks than case separations sizing this way. You do have to inspect the brass carefully when you reload to look for case problems and thats just part of the routine, for QA and for your own safety.
The 7.62x51 in the M14 is a different animal. Most highpower shooters back in the day when the M14/M1a ruled the line, would reload 4 or 5 times max then pitch the brass. The M14/M1a is one of the fastest actions in its timing and is starting the extraction cycle before the case pressure is down. So it really stretches the case body compared to an AR10, FAL, etc.

 

[1lnbrdg]

Re: Case Head Separation Lake City Brass

Yeah, what 7X57 says. Also, on top of that, Topbrass does what they call roll-sizing. While i'm not quite sure what that is, it seems to cause problems on the web area.

For me, I could only get 1 safe firing out of Topbrass thru my M1A. The next time around, I'd have casehead seperations. You seem to be doing better. My rifle is hard on brass though; I could only get 3 safe firings out of new brass.

 

[Paladin2147]

Re: Case Head Separation Lake City Brass

If you use fired LC 7.62, get a bump gauge as suggested by 7X57 - not a drop in gauge - one that gives you numbers. Set your sizer to set the shoulder back .002 or .003. from a case fired in "your rifle." That will help slow the inevitable head snap. There is a reason fired LC is cheap. I use it, but I anneal it, just the neck/shoulder and give it some loving. Still it will shit on you eventually. Just the way it is. I'm not 100% sure its worth the trouble. If you are also running it in a AR-10 as I am, keep a shell extractor handy.