.223 or 5.56?

[tatt00edangel]

I'm new to the black rifle game, I just picked up my bushmaster today. But I'm slightly confused. If there's a post for this somewhere else, please let me know. I thought that the .223 and the 5.56 were the same round. My rifle says 5.56 cal on the side and the follower on the mag says 5.56. Does that mean I have to find a specific 5.56 cartridge or is that the same as the .223?

I apologize if it sounds like a dumb question, I just don't want to fire the wrong round.

Thanks.

[GMONEY]

You can fire either one... Just don't fire 556 out of a 223 rated AR. 556 has more pressure then the 223. Oh ya use the SEARCH button...

[gimmejr]

Youll be fine firing either round.

[brando]

http://en.wikipedia.org/wiki/.223_Remington#.223_Remington_versus_5.56_mm_NATO

[Paratus et Vigilans]

You'll become an expert soon enough, and there is much to learn about ammo for the AR-15 and just about everyone has an opinion (and they're ALL right! ), but the short answer for AR's is you can ALWAYS shoot both commercial .223 and 5.56 NATO out of an AR with a chamber that is marked 5.56 as your Bushmaster is, but you must NEVER shoot 5.56 out of a rifle, AR or otherwise, that has a chamber for .223 rounds. Sooner or later that will get you a kaboom.

Assuming you have a Carbon 15 from Bushmaster (it had better not be an XM-15 as they are on the banned list and are NOT an OLL) then you will have a 16" barrel with a 1/9 twist. That is good for stabilizing a wide range of bullet weights, from 45 gr. up to 69 gr. Most AR plinking ammo is 55 gr. Keep your ammo choices in that 45-69 gr. range and you'll do fine.

Happy shooting!

[jojo760]

Just a quick question regarding this, has anyone had any problems using 5.56 out of a Rock River upper. They are chambered in Wylde, which I'm assuming is 5.56 so you can use either. According to the Rock River site you can use either round. It seems all of the uppers I've been looking at, Rock River, LMT, CMMG, or Stag, are all cambered in 5.56 or Wylde. Is there a specific brand that chambers for .223 only?

[tatt00edangel]

Thanks...

That's the answer I was hoping for. Regarding the XM-15. Let's say. hypothetically, it's a XM15 upper on a Stag lower. Is that kosher?

[odysseus]

Just a quick question regarding this, has anyone had any problems using 5.56 out of a Rock River upper. They are chambered in Wylde, which I'm assuming is 5.56 so you can use either. According to the Rock River site you can use either round. It seems all of the uppers I've been looking at, Rock River, LMT, CMMG, or Stag, are all cambered in 5.56 or Wylde. Is there a specific brand that chambers for .223 only?

Most all AR's are chambered like you mention and accept 5.56. They exist I guess, but I have never run into a strictly .223 SAMI chambered upper for an AR.

As said here - don't do 5.56 in a rifle chambered strictly for .223. Most .223 bolt rifles being an example.

.

[Lon Moer]

All questions will be answered by the Ammo Oracle.

[Paratus et Vigilans]

That's the answer I was hoping for. Regarding the XM-15. Let's say. hypothetically, it's a XM15 upper on a Stag lower. Is that kosher?

Yeah, you're safe. It's the XM-15 lower that's on the list here in CA. The uppers aren't an issue, unless you mate a ceratin RRA upper to a certain RRA lower and you may thereby create what could be construed as a listed banned AW. But you're good with the Bushmaster upper and the Stag lower.

So, is your Bushmaster upper 16" or 20"?

[tatt00edangel]

Thanks, it's a 16". Bought it here through a calgunner.

I'll probably be asking more questions, so bear with me. This is a forum is a great service to us that are new to this.

[BlackReef]

tatt00edangel -

Welcome to the Black Rifle world! It's addicting!

Enjoy CalGuns

[tatt00edangel]

Thanks

[aplinker]

the Ammo Oracle article is good

Almost all modern rifles are just fine with 5.56 even if they say .223 - but I'd call the manufacturer first.

The only difference in the rounds themselves is pressure. 5.56 being higher powered.

A large portion of 5.56 marked barrels for ARs are actually chambered in .223.