5.56 vs. 223

[mek42]

If I am reloading once fired LC brass from the mid-late 70's (presumably 5.56) with 223 dies, will a 223 barrel work?

Thanks!

 

[amlevin]

I have loaded well over 5,000 rounds using LC brass. Trimmed to 1.750", sized with a .223 Rem Die, and loaded to SAAMI specs, it will work great in any .223 bbl.

The Brass is pretty much the same although a little "heavier" than some civilian brass.

 

[mek42]

That is what I thought, but am planning to build an AR and am reading about 5.56 will also shoot 223 but not the other way around and figured I'd check first.

I might not have the whole AR by the end of the summer, but hope to do some 223 shooting with my contender.

Again, thanks!

 

[ftierson]

In my experience, commercial .223 cases and military 5.56x45mm cases have almost identical case capacity and can be used pretty much interchangeably.

However, such a situation does not exist for .308 Win. and 7.62x51mm NATO cases, and for commercial .30-06 compared to military .30-06 cases. In both of these instances, the military cases are 'heavier' with less case capacity, and powder loads must be reduced somewhat in the military cases compared to the commercial ones...

By the way, mek42, where are you located (at least vaguely) in upstate New York? I grew up in Newcomb, New York, in the central Adirondacks...

Forrest

 

[ocabj]

I agree that Lake City .223 brass is basically the same capacity as commercial brass. The only brass that I have come across with less capacity is Lapua. You definitely need to drop the load by at least half a grain if you developed for LC or another commercial brass and switch to Lapua.

 

[Jacka L Ope]

I believe this article is still relevant:

Similar but not the same...

5.56mm v. 223 Remington

Deconfusing the issues of a couple of differences...