.223 v 5.56 Nato. The difference being...?

Those believing both rounds are the same should check out reliable sources for peak pressure specs. They may be surprised.
 
Last edited:
SAAMI's for the .223 is 55,000 psi while MIL SPECS for the 5.56 is 62,400.

Really!!

See US Army TM 43-0001-27, chapter 10:

http://www.hk94.com/hk/topic/26614-...mmunition-data-sheets-for-small-caliber-ammo/

i can find one case where rifles blew up using .223/5.56mm ammunition. Those guns were destroyed while firing Winchester Power Point .223 ammunition:

http://bulletin.accurateshooter.com/2011/03/winchester-recalls-223-rem-64gr-power-point-ammunition/

More:

http://www.thefirearmblog.com/blog/2011/03/04/winchester-5-56-ammunition-recall/

On 02/14/11 an officer was attending an M4/MP-5 class and during a shooting session, the .223 rifle (Stag Arms) experienced a catastrophic failure resulting in an upper receiver cracking and the bolt being pushed into the bolt assembley.

During a SWAT training day on 02/23/11, three more M4 style rifles experienced a catastrophic failure at the same time. All three rifles experienced the bolts being pushed into the bolt assembly, the upper receivers were cracked and / or broken apart, and the lower receivers were bowed outward. The ammunition we used in all the rifles were Winchester RA223R2 Ranger 64 gr. Power Point.

The Rifles were: 1-Colt, 2- Bushmasters and 1 – Stag Arms
 
The above examples are ammo problems, not 223 vs 5.56 problems

Supposedly 223 ammo is safe in either 223 or 5.56 chambers. The alleged problems are when 5.56 ammo is fired in 223 chambers.

All the examples above were from defective 223 ammo fired in 5.56 chambers. That ammo would have caused problems in any gun.

The problem is greatly overstated. There are minor differences between the 2 rounds and in chamber specs, but if you check out any other commercial chambering you will find differences just as great. Same with chambers in different guns.

Lots of talk about different chamber pressures. My loading manuals show anywhere between 27,000 psi up to 60,000 psi as a max charge in 30-06 depending on the load. I've found a few factory 30-06 loads that simply would not fit in the chambers of certain rifles if you happen to get a rifle with a chamber cut on the minimum side and ammo a little on he large side. We could easily have 2-3 different designations for 30-06, but we don't.
 
i've weighed thousands of cases and never found US military 5.56mm cases to be thicker/heavier than US commercial .223 cases.

This has been my experience also.

A few things should be kept in mind when over thinking this issue. One is that you have to trim the cases before weighing them so there is some uniformity to begin with. Another is that the difference between chambers is very likely talking about bolt action rifles in 223 vs semi autos in 223/5.56.

My AR eats any brass, my M1A eats any brass. All my ammo is handloads excepting the occasional surplus military ammo. I wont shoot commercial 308 Win ammo through my M1A.
 
A bit about chambers, don't know if this is on topic or not but file it in the "for what its worth department"

Lot of talk about 223 chambers being tight vs the 5.56 chamber. Don't know for sure, I can only report on my chambers.

I have a Mann Accuracy Device (used by the military for testing ammo) I obtained from the CMP. Remington Action and Kart Barrel.

It's a TIGHT 5.56 chamber. If it isn't clean, it wont accept a 223 "go" gage.

About 1/3 of the pieces of new Winchester 223 brash wont chamber in the Mann device. It chambers in my two ARs and my Rem 700 Bolt gun.

I have to resize the new brass with a SB sizing die to use it in the Mann Device.

If I fire any ammo in my two ARs the brass wont chamber in the Mann Device. However if I fire ammo in my Remington 700 Varmint, I can get it into the Mann Device.

This Remington BDL Varmint is the rifle I carried as a LE Counter-sniper rifle. Got it in 1978. The ammo I carried and used in that rifle was M-193 5.56.

I shot it quite a bit wanting to keep in practice and constantly confirming zeros.

I had access to a lot of M193s back then and that's about all I shot. But the chamber is still, after nearly 35 years, the Remington Chamber is still tight enough to get the spent brass in my super tight Mann Chamber.

One of my ARs is a SP1, I've had it a while and have shot thousands of M193 out of it.

My other AR is a White Oak Service rifle. I got it later in life when I had to furnish my own ammo. Can't tell you much about it and M193, only fired a few rounds I found laying around.

This doesn't prove anything to anyone but me. I don't care what I shoot in my 223s, be it 223 or 5.56, in my rifles.

Do what makes you feel better.

We all have different opinions, That's good, if that wasn't the case we wouldn't have anything to talk about.

I doubt I get any more 223s, and I highly doubt I'll go back into the NG where I can have access to 5.56.

I'll just keep hand loading what ever ammo my rifles like and shoot accurately.
 
Excellent information Capt Kraig... and also from Thallub.

I have been under the mistaken impression that there was a small (but important) difference between 5.56 and 223, based on internet chatter. Not that it mattered to me, since my AR is the only rifle I have in 5.56/223.

This thread has been very informative. Thanks!
 
Back
Top