5.56/.223--Not the same??

Monofletch

Monofletch

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I have a new AR15 chambered in 5.56. I always thought 5.56 and .223 were the same - some say no way. Can I shoot .223 in my 5.56? Anyone know?

I know this is a knife forum...sorry guys.
 
Here is a pic of the side of my new AR. Notice it says Cal. Multi 2012. In the book it says na na- they are different. The 5.56 is thicker cased and has longer lead with much higher chamber pressure. Now I'm confused. I guess the AK would have been a wiser choice.. I already have several 7.62x39's!
 
Monofletch said:
I have a new AR15 chambered in 5.56. I always thought 5.56 and .223 were the same - some say no way. Can I shoot .223 in my 5.56? Anyone know?

I know this is a knife forum...sorry guys.
Click to expand...

Came here looking for knife stuff and saw this post. If your rifle is chambered for 5.56, YES you can shoot .223 from your 5.56 guns. Generally 5.56 has more pressure than .223.

I have two rifles chambered in 5.56 and I have shot well over 5000 rds of .223 through them.

Hope this helps.

Just want to caution people saying they are the same. They may chamber just fine in a .223 rifle or 5.56 rifle, but as mentioned before, 5.56 casings have thicker walls which creates more pressure when fired than a .223.

Could your fire 5.56 in a .223 gun? Probably. Should you shoot 5.56 from a .223 gun? I wouldn't.
 
Kinda the same round. You can shoot 5.56 and 223 in a 5.56 chamber, but only 223 in a 223 chamber. The 5.56 is loaded to higher pressures and could cause damage in a gun with a 223 chamber.
 
Dimensionally they are the same but as stated earlier there is a small difference. You have a 5.56 so you will be ok to fire .223 but a rifle chambered for .223 can but should not fire 5.56.
 
Straight from the manual that came with my rifle---
There is a difference in the chambering between a .223Rem and the 5.56 X 45 NATO rounds. Without going into minute details-- 5.56 was developed for use with military bullets Because of this the head spacing is slightly different from the civilian .223 Rem. The lead chamber is longer to accomodate the longer steel core military bullets and the brass is thicker because the cartrige is loaded to much higher pressure UNDER NO CIRCUMSTANCES should you fire 5.56 x 45 in a rifle chambered in .223 Rem. However, the opposite is true: you CAN SAFELY FIRE .223 Rem ammunition in a firearm chambered in 5.56 X 45.

Wish I would have read this earlier.
 
Monofletch said:
Here is a pic of the side of my new AR. Notice it says Cal. Multi 2012. In the book it says na na- they are different. The 5.56 is thicker cased and has longer lead with much higher chamber pressure. Now I'm confused. I guess the AK would have been a wiser choice.. I already have several 7.62x39's!
Click to expand...

Mono,

The lower of your AR has nothing to do with the chamber. You need to check the barrel to see what it is actually chambered in. Should be stamped on the barrel somewhere. AR lowers sometimes come in Multi Cal because the lower might be attached to an upper that is not 5.56.

Good luck.
 
Thats what the maufacturer just e-mailed me. Mine (by ser #) is 5.56.. He said they only chamber in 5.56 because of the ammo issues.
 
This is basically a 9mm Luger, parabellum, nato, .... type situation. If you are chambered for the higher pressure round, you're generally okay to shoot any of them. If you have unusual bullets (steel, long, extra heavy, extra long, ...), it's best to verify compatibility first.
 
Yeah,5.56 higher pressure.You can shoot .223 in a 5.56 but not the other way around.
 
The only difference is something called the leade. Leade = "distance between the mouth of the cartridge and the point at which the rifling engages the bullet." The .223 has a shorter leade than a 5.56, so some rifles chambered in .223 may have an over pressure issue if you fire 5.56 through it. Most semi autos are chambered in the 5.56 regardless of what the receiver says. I would mainly be worried on high precision and bolt action rifles since their chambers have extremely tight tolerances.
DuPont had an excellent article on this but I can't find it for the life of me. Here is a wiki page, the info is almost the same.
http://en.wikipedia.org/wiki/.223_Remington

Firing .223 out of a 5.56 is safe. If you fire 5.56 out of a .223 chambered rifle you need to check for over pressure. Easy way to check is fire both and check the spent brass, if there are powder stains near the primer then stop shooting the 5.56. The rifle won't blow up but you can foul the action if you continue to shoot the incorrect cartridge.
 
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Gunsnknives said:
These are the same cartridge. Your understanding is correct.
Click to expand...

Not really.

You can shoot the .223 in your 5.56.

The reverse is not true.

5.56 has a longer lead (neck) and the nato rounds are higher pressure. You should absolutely not shoot 5.56 in a gun that says it is chambered for .223!!!!
 
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