[d4an6]

Just wondering what is the difference in military and regular 223 aumo?

[canebrake]

There is no .223 military ammo, it's called 5.56 NATO and yes, there is a difference.

[MrWray]

Ammo? Military uses the 5.56nato, the civilian version is .223. The .223 is the "toned down" version of the military 5.56nato..shooting .223 ammo from a 5.56 chambered rifle is fine, shooting 5.56 ammo through a .223 rifle "can" damage some rifles

[303tom]

These are rifle bores, Military & Civilian.



420 Rds. .223 (5.56x45 Mm) 62 - Gr. M855 Ammo With Can, Ammo Rifle, Lake City at Sportsman's Guide


http://www.midwayusa.com/Product/789567/lake-city-ammunition-556x45mm-nato-62-grain-xm855-full-metal-jacket-10-round-clips-in-ammo-can-of-420-14-boxes-of-30

[d4an6]

Just got a rossi 223 yesterday, why was asking they told not to put military grade ammo in it, first gun I bought, thanks for answering my question.

[spittinfire]

What often happen when firing 556 in a 223 is that the barrel throat actually gets eatten out from the additional material and higher pressures.

[axxe55]

Originally Posted by d4an6

Just got a rossi 223 yesterday, why was asking they told not to put military grade ammo in it, first gun I bought, thanks for answering my question.

this is the civilian chambering, only use the 223 ammo and not the 5.56mm ammo. some rifles in 223 can chamber the 5.56 ammo but it is made to work at a higher pressure and could cause problems. so the best way to avoid problems is don't use 5.56 ammo in a rifle chambered for 223. good luck.

[Snakedriver]

It varies between the different manufacturers on this matter. Ruger Mini-14's (except for the Target Model), while marked as .223 Rem. actually have a 5.56 NATO chambers and it states in the Owner's Manual that it is safe to use either ammunition in those guns.

5.56 NATO ammunition is generally loaded to a higher chamber pressure than the .223 Rem., so the general rule is to not shoot it through a .223 Rem. Rifle. If you have doubts about your rifle's ability to use it contact Rossi Customer Service and discuss it with them. I'm sure it won't be the first time anyone has ever asked the question before. They'll be able to tell you for sure if it's safe.

The reverse is true, that if you have a 5.56 NATO chambered rifle, a .223 Rem. round is just fine to shoot through it.

[axxe55]

the cartridge dimensions are the same, but the difference is in the pressures generated when fired. now the chamber dimensions are different between the two. also some say that military brass is thicker than commercial brass, but this is not something i know to be fact. (this is even stated in several reloading books i have, and they state if using military brass, to start at the lower powder charges) my Bushmaster is chambered in 5.56 and i shoot 223 through it.

[alsaqr]

.223 Remington cartridge case dimensions are identical to 5.56mm case dimensions. The original .223 chamber has a shorter leade than the 5.56mm chamber. A gunsmith friend tells me that no one currently makes a gun with a .223 SAAMI chamber. In any event there are 10-12 different .223/5.56mm chambers.

http://ar15barrels.com/tech.shtml

It's a myth that 5.56mm US military cases are thicker than .223 cases. It's also a myth that the 5.56mm develops more pressure than the .223.

See Army TM 43-0001-27, chapter 10.

www.dtic.mil/dticasd/sbir/sbir032/a044a.pdf