If the barrel is stamped for 5.56 ammo, can it also shoot .223 ammo?

Yes, if it has a 5.56 chamber, it is also safe to shoot .223.

It might be possible to shoot 5.56 from a barrel stamped .223, but you would need to check with the manufacturer first.

Yes, but the reverse is NOT recommended.

Depends... For example, my Ruger Mini 14 is marked .223, but Ruger states that it is fine for 5.56mm. Some older AR-15s are marked this way as well.

Best to check with the manufacturer. Best practice with any rifle is to check the barrel markings and use the caliber stamped on the barrel. A barrel chambered for 5.56 NATO can fire its parent cartridge, the .223 Remington. In most cases a barrel chambered in .223 Remington can not fire a 5.56 NATO cartridge.

Why? 5.56 NATO generates more pressure than .223 Remington. A .223 Remington has a different chamber leade than a 5.56 NATO chamber leade.

There are some instances such as Cyphertext mentioned where the barrel is stamped .223 and the manufacturer explicitly states their .223 stamped barrel can fire 5.56 NATO. This would be the only instance where I personally would do this. I always err on the side of caution.

To add another bit of info, a .223 Wylde which is a .223/5.56 hybrid chamber that can fire both. http://en.wikipedia.org/wiki/.223_Wylde

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-John

My Mini 14 (181 series) is stamped 556 on the top side,on the rear of the upper where it meets the wood. The manual also says 556 is good to go.

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You sure? I dug mine out and looked and it is marked .223 on rear, 187 series.

Can you guys stop talking about the Mini-14? Ever since watching the A-Team on T.V. when I was a kid, I've wanted one.

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-John

Why? So you can miss everything you shoot at like on the A-Team?

I really don't know much about the one I have. It is one of the rifles that I am supposed to be selling for my father in law...ya, like that is going to happen!

From just looking around the net about it tonight, I found that it has a 1:10 twist barrel, and it is a Ranch Rifle. I took it out to shoot last spring, and at 50 yards, I couldn't hit a tree stump. Guess it doesn't like those 62 gr Silver Bears. I'll have to get some decent 55 gr ammo and take it to the range.

I discounted the Mini-14 for a few years because it was less accurate than an AR-15. From what I gather, Ruger re-tooled the Mini-14 manufacturing equipment. That tightened up clearances and brought to bear modern manufacturing advancements. New production Mini-14 owners report accuracy on-par with an AR-15.

To keep this forum specific... I'd be curious to see some comparison targets between a M&P 15 and a Mini-14 using the same ammo and iron sights.

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-John

Yep, the new ones are supposed to be better. The ones that Max and I have are over 20 years old.

Sorry for the thread hijack aaa8shot. Hopefully you don't mind since your question was answered.

Positive and I'm looking at the old (181) manual. It says: Ammunition .223 (5.56) caliber in the manual too. Has a 18.5" barrel,6 groove RH Twist One Turn in 10. Muzzle Velocity 3,300 fps Muzzle Energy 1330 ft. lbs.

It says... "It is specifically designed for the .223 (5.56) caliber U.S. Military and commercial cartridges".

It likes it's ammo on the hot side pushing the 3300 fps with 52-53 gr. BTHP's or 55 gr BTFMJ bullets. Found it likes 4895 powder the best.

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I wonder why they would mark one series as 5.56 and another as .223? Could it have been politics, as 5.56 would be a military round and .223 a sporting round? Hmmm, more Google time.

The Ranch Rifle was where/when the BIG down fall started. Also the 7.62x39 was a GIANT dud for ammo. We wanted a 7.62x51 (308) model,they did show one in a very early catalog but it never went into full production.

Only reason I was shooting Military surplus 5.56 was to get the brass for reloading (and back then it was DIRT cheap),didn't group worth a ****,but you could hit 12"x12" steel and pot mark it at 200-300 yards with the 55gr FMJ's. Once you got the reloads dialed in, it was a great shooter and would hold it's own (at least the 181 and old 180 series did) up against any other semi auto. Mine would walk all over any AR's back in the mid/late 70's. My 181 was born in 1977, so it's 37+ years old and still ticking. Also, I NEVER did any "heavy" mag dumps, it's never failed me in ANY weather conditions under any extremes and (it's one shot) busted many a coyote over the years.

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For the times, it could have been a liability thing too. ??? I don't think the "Evil Black Rifle" fraze craze had started quite yet.

I think another reason I had such a "good one", was it was still all new tooling.

When I got the Mini,there were two on the wall. A 180 and a new 181. Ruger had upgraded and added a bolt lock cover plate to the side of the 181. The 180's bolt lock assembly was open and I thought that looked like a possible "dirt problem" area... So I grabbed the 181. I replaced the upper hand guard assembly with a vented one and also added a heavier recoil spring.

I "think" they added the slide assembly finger guard on the 182. Lost track of them after that.

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Interesting read on this subject:

http://www.luckygunner.com/labs/5-56-vs-223

James

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