.223/5.56 cases

[JimMc]

I have been forum bouncing and I came across a post telling the inside deminsions of the 5.56 is smaller that the .223. How in the world would you tell which brass you have whether it be 5.56 or 223?

[stevec]

The headstamp is marked 5.56 or .223

Steve

[hitman49]

If there is no caliber stamped on it then it is prob mil-surp brass and it is 5.56

[Tightgroups]

In case you dont know the difference and why, weigh them both on your powder scale, you will find the 5.56 is heaver than a commercial 223 case, it has thicker case walls. The 5.56 is designed to be stronger for use in machine guns, that eject and reload the chamber vary quickly and violently. A 223 case might just get the head pulled off the case during ejection.
The 5.56 case wont hold as much powder as the 223, all due to the thicker case walls. also the 5.56 will have the primer staked in with either a 3 point stake or ring type stake, that you should remove before you reprime.

[GaCop]

If you load for an AR rifle with a standard 5.56 chamber/mil spec barrel, the military brass will last much longer than commercial. As stated, the crimp has to be removed during the first reload in order to seat primers.

[Three44s]

I don't particularily worry about the headstamp ....... but I do sort by it and load specific to it.

If I switch from commercial brand X to a particular mil surp case ..... I treat it like a new load and redevelop it.

The above is for my bolt gun in .223

I would suggest weighing your mil cases and commercial ones to verify that the military brass is in fact heavier.

I have not weighed mine but will take it into consideration with handloads in my AR's.

Three 44s

[Bad Water Bill]

I am working 223 brass. The head stamp is FC 06. The primers are crimped and sealed with red sealer. Gee would you think they are military? You can bet your bottom dollar they are. Also a warning. Since weight has been discussed already I will mention that you should ALWAYS use less powder in any military case as they all have less case capacity. Using a max 223,308 or 30-06 load in a military round will get your attention if you survive.

In my project I end up with a 20 Varmint/target and the military cases have 2 grains less capacity than commercial cases. That is about 10% less space and when you only have space for 20 grains in a commercial case it will be bad news. Always reduce weight when using military cases please.

[GaCop]

I'm using some of the FC 06 cases in my M4rgery. They work well and have produced some accurate loads at 100 yards with H322 and 60 gr V-Max.

[red_zr24x4]

90% of the cases I own for .223 and 30-06 are military, just treat it like a new load development and your gtg.
I hardly ever use a max load anyway, especially in the 06 which I shoot out of a Garand