5.56 or .223?

[JOERM]

Going to purchase a new AR and want to know what cal is best. 5.56 or .223.heard so many stories that you cannot shoot 5.56 in a .233 but can shoot .233 in 5.56. Isn't the only difference is the amount of powder? Please enligbten me. I really want to buy a new AR. Walmart has one on sale right now.

 

[breakingbad]

5.56 case neck is something like 1mm longer ... it's possible a 5.56 round would misfeed in a chamber sized for .223 if the tolerances stack up the wrong way

just play it safe and get 5.56 gun ... nowadays there is no difference in cost

 

[Black_Sheep]

.223 Remington - Wikipedia, the free encyclopedia

 

[HotRoderX]

My understanding is the 223 cartridge has a little shorter neck I think it then the 5.56. Trying to fire a 5.56 round out of a .223 can cause the gun to go boom. I would say your ill advised to try using 5.56 in a gun marked .223 only.

I would also vote getting a 5.56 rifle that way you have versatility to fire what ever you please.

 

[jagen heie]

was looking at some ar15's the other day and under caliber it actually said .223/5.56 thinking at this point theyre interchangeable

 

[jaykellogg]

Get a Colt. WalMart has some Colts, but for many reasons Colt is the best pick. There are sites out there where you can order LE marked Colts for around $1000-1050

 

[Bello]

My ar clone is the colt match target, in jersey it's illegal to have it say ar-15

 

[steveno]

the difference between the 5.56 and the 223 is the leade in the chamber. the 5.56 uses a slightly different bullet shape and requires the different leade. you can shoot the 223 in a 5.56 rifle all day long. there could be some big problems by shooting 5.56 in a 223 rifle. I think the 5.56 has a little higher chamber pressure also.

 

[kraigwy]

It depends on what gun you have. All my 223/5.56 guns are pre internet. Before the internet told us they weren't interchangable our guns didn't care. No guns blew up, no one was killed shooting 223s in a 5.56 or a 5.56 in 223

Now though, if you use a 223 in a 5.56 or a 5.56 in a 223 you'll bring on the raft of the internet gods and all your guns will blow up.

Same with the 308 vs 7.62.

Just be thankful we have the internet to protect us and our gun.

 

[kudzu3]

It depends on what gun you have. All my 223/5.56 guns are pre internet. Before the internet told us they weren't interchangable our guns didn't care. No guns blew up, no one was killed shooting 223s in a 5.56 or a 5.56 in 223

Now though, if you use a 223 in a 5.56 or a 5.56 in a 223 you'll bring on the raft of the internet gods and all your guns will blow up.

Same with the 308 vs 7.62.

Just be thankful we have the internet to protect us and our gun.

My thoughts exactly. I have bought shells that read "223/5.56mm". .223 is measured in inches, 5.56 is measured in millimeters. the way I see it, that's the only difference.

 

[Alk8944]

As has been said before, the cartridges are identical and fully interchangeable. 5.56mm is the military designation and .223 Remington is the civilian designation. The difference is in chamber dimensions, the military chamber has a longer throat than the civilian SAAMI chamber.

Many civilian chambers have the military throat dimensions and can use military spec. ammunition without problems. If you were to do the unthinkable and read the owners manual that came with your rifle the manufacturer will tell you if shooting military ammunition in it is a safety concern! But why would you want to read the documentation that cane with a gun???????

 

[Arik]

It depends on what gun you have. All my 223/5.56 guns are pre internet. Before the internet told us they weren't interchangable our guns didn't care. No guns blew up, no one was killed shooting 223s in a 5.56 or a 5.56 in 223

Now though, if you use a 223 in a 5.56 or a 5.56 in a 223 you'll bring on the raft of the internet gods and all your guns will blow up.

Same with the 308 vs 7.62.

Just be thankful we have the internet to protect us and our gun.

Yes and no. While basically its true it also depends on the rifle you are shooting. The 308 win has higher pressure especially in hunting loads.There are a lot of surplus military rifles floating around that cant handle those loads. Partially because of their design or metallurgy and partially cause they are USED!

For instance, if you are shooting 8x57 or 7x57 (8mm or 7mm Mauser) most commercial ammo like Remington are under loaded because they try to stick to what was factory loading for its time. Otherwise your rifle might go KABOOM. Same with the 6.5x55 Swede. Great all around caliber. Flat shooting, accurate, has distance, able to take down most animals in N. America but if youre shooting a say a Carl Gustaf Mauser insted of a modern Tikka rifle youre better off sticking with factory specs and not modern loadings.

Also not all marking on guns are accurate. Colt only makes 1 type of rifle in many different variations but some like my say 223 on the mag well even though its a 5.56

 

[Mike7.62]

Going to purchase a new AR and want to know what cal is best. 5.56 or .223.heard so many stories that you cannot shoot 5.56 in a .233 but can shoot .233 in 5.56. Isn't the only difference is the amount of powder? Please enligbten me. I really want to buy a new AR. Walmart has one on sale right now.

Buy the 5.56. It's a hair longer in length than the commercial .223, and you will avoid the max .5.56 round entering a min .223 chamber and possibly causing a mishap. It's rare, but it does happen once in a blue moon. With the 5.56 you can shoot either with no worries.

Does the one at Wally World have the 5,56 or the .223 chamber? You didn't specify. If it were me, and the price was right I might purchase it if it were .223 and get a new upper in 5.56 from a good source, or re barrel it in 5.56. In speaking with my dealer yesterday, he tells me that post election, AR's of any stripe are becoming hard to find, and after yesterday's tragedy in CT, I expect political emotions to be running high to "do something", even though AR's played no role in the unhappy events.

edited to add: If you buy an AR, get as many high capacity MilSpec or MagPul magazines as you can. It's money in the bank. I remember the last time we had a ban, prices went through the roof and availability went way down. Not saying that it will for sure happen again, but better safe than sorry. Here's a good source:

http://www.44mag.com/default.asp

 

[mkk41]

Some rifles will say .223 Rem on the barrel , but in the owners manual , say that they are designed to take .223 Rem commercial and 5.56 NATO-spec ammo.

For example , The Ruger Mini-14 is marked .223 Rem on the barrel , but manual says as above.

 

[Art Doc]

I have been hearing/reading this debate go on for years. Same with the .308/7.62 calibers. I am no expert but here has been my experience.

In all of my .223 rifles, self-loaders and bolt action, commercial .223 and military 5.56 loads, feeds, shoots and ejects with no discernible difference. If there is any difference between .223 and 5.56 I cannot detect it in my rifles.

Ditto for the .308 and 7.62x51.

That's all I know.

 

[mkk41]

I have been hearing/reading this debate go on for years. Same with the .308/7.62 calibers.

That's all I know.

Actually , .308 Winchester SAAMI pressure limit is higher than 7.62 NATO. Something like 5000 psi or cup higher.

 

[johngalt]

Technically, you are not supposed to shoot 5.56 in a .223. 5.56 chambers have a longer leade to accommodate longer bullets. 5.56 can also be slightly higher pressure.

However, I shoot 55 gr 5.56 in my M70 all the time. I don't believe for an instant that an AR-15 has a stronger receiver than a M70.

 

[LouisianaJoe]

I have a Thompson Contender with a Super 14 barrel in .223 Remington. I fired some 5.56 NATO rounds in it and the extra pressure of the 5.56 caused the primer to partially blow out of the case and it made it difficult to open the gun after firing. I make sure that I am firing .223 Remington in it now.

See
https://en.wikipedia.org/wiki/.223_Remington
and
https://en.wikipedia.org/wiki/5.56%C3%9745mm_NATO

Both links have a discussion on the differences in the 2.


Note that the maximum pressure for the 5.56 is 62,366 psi and the .223 Remington is 55,000 psi.

 

[Rule3]

Just buy one that says 5.56. Done.

 

[NFrameFred]

A little knowledge can be a dangerous thing . . . especially for some people.

The cartridges are interchangeable and yes there is a slight, insignificant dimensional difference.

Any problems in these or the 30 caliber have generally come from folks using cheap made no-name parts in their guns and cheap thrown-together guns with poor head spacing with military issue/grade ammo that was loaded for machine guns.

For those who want to worry about it, buy one chamber marked 5.56 and forget about it but it's basically a non-issue.