Aluminum casings?

[last bastian]

I keep trying to do a search to see if this topic has already been discussed but for some reason it won't let me. Anyway. It seems like aluminum would be cheaper to make casings out of, so why are casings mostly made of brass? Brass must be better for some reason?

[kmrtnsn]

A company a few years back toyed with the idea of plastic cased ammo, cheaper still. Militarymorons reviewed it a few years ago on their site.

[SpinRC]

I know that a lot of research on aluminum cased ammunition was done in the 60's and 70's but nothing ever came of it. The British tried it out when they were developing the 280 British cartridge and they even produced some aluminum cased ammunition for it. The U.S. also experimented with aluminum casings for the 6mm saw round.

In 1972 Frankford Arsenal did a feasibility study on using aluminum cased 5.56 ammunition in M16's. They had some problems with burn through on the casings but with further development they were found to be acceptable. The study was done by Reed E. Donnard and Thomas J. Hennessy.

I do not know exactly why aluminum casings are not more widely used but I would bet it's because the extra steps involved in processing the cases and the special aluminum alloy that has to be used brings the price up to the same level as brass.

[rat31465]

Aluminium casings are known to be somewhat difficult to extract. Brass has a natural Lubricity to it that cant be matched with aluminium. At least that is my understanding of this issue.

[Byron]

Nevermind, I just realized this was a discussion about reloading... not about shooting commercial ammo. Sorry 'bout that.

[larry0071]

I would guess that allum may not swell and seal as effectively as brass, and also may retain more of the swelled dimension after the combustion process ended... resulting in a tighter case in the barrel for the extractor to deal with. I could be totally wrong, I am just thinking out loud.... no scientific bases what so ever on my theory!

I would also continue to ponder with some of the "super lubes" dry film lubricants that science has allowed us, maybe by trying to team up modern engineering, modern software, and modern dry film lube technology... the problem could be easily worked out. Now you got me wondering why no one is pushing the issue!

[SMJayman]

CCI Blazer aluminum cased ammo works fine for me. I believe it does have some sort of coating on it to improve extraction. I've talked to people who have even reloaded it, although I'd be wary of doing that more than once and I wouldn't do it with a very hot load.

I've never seen it done with rifle ammo though. I have seen the plastic cased rifle ammo, and even shot some of it. It wasn't very hot as compared to M193, I expect because the case couldn't take as much pressure, but that is purely supposition on my part.

[ramrod]

I have reloaded the blazer cases once, u just have to check each case for cracks.

[rat31465]

The last time I shot Blazer Ammo it wasn't reloadable due to a proprietary Priming system similiar to Berdan Primers... How did you get around that?