.223 vs 5.56mm and where to buy...

[silent_killer]

First off, I would like to say hello to everyone, my Name is Scott and I am new to this forum. I look forward to talking to members of this board, you guys/girls seem to know your stuff.

Ok here is my question. I just picked up my first assault rifle (im used to bolt action sniper rifles, long range rifles) Its a Bushmaster XM15-E2S M4. I know that .223 and 5.56mm cartridges are close to the same but not quite the same.

Bushmaster recommends the 5.56mm over the .223 but says you can use either with no problems.

Now here is my question, where the hell can I buy 5.56mm? All the gunshops local to me that I call say that .223 and 5.56mm are the same, I know there NOT.

I am new to this type of cartridge so I need some insight. But to my understanding since the 5.56mm is a NATO cartridge it is Milspec and more than likely is higher power and good for better velocity. So with that I am assuming also more expensive. Which I can reload my own so that wont really be a problem.

So can I get some pros and cons of .223cal and 5.56mm with my particular rifle. And where to buy 5.56mm.

Thanks in advance everyone.

PS. I tried searching, but nothing really answered my questions.

 

[Tommygunn]

5.56mm. is a tad more powerful, and IIRC there are slight variations in dimensions, but not much. I think the brass on 5.56mm. is thicker, too.
I have obtained a lot of ammo through Cheaper than Dirt.
www.cheaperthandirt.com
The prices are going up -- and availability is ... >NOT< to put it bluntly. Stock up where you can.
Other posters will no doubt have other and maybe better places to get ammo.

 

[Larry Ashcraft]

Welcome to the forum!

I can't answer your questions, but I'm moving this to rifles where the experts are.

 

[Joe the Redneck]

OK, the big issue is pressure. The ammo industry decided what the upper pressure limit of a given cartridge will be.

.223 and 5.56 have different pressures.

When a gun is "proofed". a special cartridge s made that far exceeds the set limit and the gun is fired. If it doesn't blow the gun up, the barrel has been "proven" safe and life goes on. The idea is that if a gun doesn't blow up at say, twice the pressure. This way if a cartridge is a little over pressure, no one is going to get hurt.

Now others are going to disagree with me on this, so you make up your own mind. But I feel this was much more os an issues in the old days than it is now. When smokeless powder came into use, the industry had a big problem. With plack powder, you basically filled the case to get good combustion. It is a low pressure explosive so this was safe. BUT, if you took your trusty old 45-70 (which meant a 45 caliber bullet loaded with 70 grain of black powder) and loaded it with 70 gains of smokelss, well, lets just say all your troubles would be behind you very quickly. You gun would blow up and send whopping big hunks of metal through your head.

This was way they needed to set pressure standards. If you buy a 45-70 off the self. the idea is that it would be safe in a weak action (like a Trapdoor Springfield) or a stronger action (like a Marlin Lever action). This creates a problem. Many of our older cartridges (like the 45 Cold of the 45-70) perform a lot better in modern weapons. Some companies will make special rounds that say "For Use in Ruger Revolvers only!" Shoot it in your Blackhawk, no problem. Stuff it in Grampas Spanish made revolver clone, you new nickname will be "lefty." This is a real issue and not to be taken lightly.

Now, just to muddy the waters even more, our military rounds tend to make jim-dandy sporting rounds as well. Lets look at the NATO 556.

It started out life as the Remington 222. This was an off the shelf round that the military was playing around with. The shortened the neck a bit, blew out the sides and the 556 NATO was born. Military rounds have to work in automatic weapons and they have to work all the time. Generally, the more "oomph" a round produces, the more reliable it will function. Military ammo is made for military guns. It doens't have to be safe in all weapons, just the ones the military is going to use.

This is where is gets tricky. If the 222 was a good varmit round, every one thought the 556 would make a good varmit round too, which it does. So the ammo makes responded to the demand and created the .223 Remington. Now, most varmit hunters use bolt action rifles. Varmit rifles also have special barrels and close tolerences to insure top accuracy. If you take a 556 NATO (which runs a bit hotter) and put it in you precision varmint rifle, it's going to put strain on the barrel and the mechenism. If you do it a lot, you are going to end up with a $1000 rifle that shoots like a $150 rifle.

I am 38 years old. I have been readin gun magazines, gun books, and shooting since I was 14. The idea that it was "unsafe" to use NATO ammo and civvie rifle and vice versa is news to me. I never knew this was even considered and issue until about a year ago. Like any other machine, if it has to work harder, it will accelerat wear, but I have never hear or read of anyone being injured by the practice. Maybe others have, maybe the shooting ranges of America are litterd with the bodies of men who have died by firing a 762 NATO in their Winchester 308 turnbolt. I don't know. I could be wrong , but I've never heard of it.

Now, as you have a Bushmaster, which is built to NATO spec, any sporting ammo you buy is going to be lower pressure. The only issues you may have would be reliability. It may not cycle if it is too gentle.

In the end, it's up to you. For ultimate saftey, NATO in NATO, civi in civi. I have a bushmaster and I have shot everything in it with no problem what so ever. I wouldn't worry about it. Just shoot decent ammo and you should be fine.

Rmeber, others disagree, you decided for your self.

 

[RNB65]

You want answers? The Ammo Oracle has answers --

http://www.ammo-oracle.com/body.htm

Most of the commercial loadings are in .223. 5.56mm is usually military surplus. Due to the ongoing wars in Iraq and Afghanistan, there isn't much 5.56mm milsurp ammo to be found these days.

Ammoman, AIM Surplus, and Cheaper than Dirt are good places to watch for surplus ammo. If you see any, buy it fast cause it won't last long.

http://www.ammoman.com/
http://www.aimsurplus.com/
http://www.cheaperthandirt.com/default.asp

 

[Owens]

Silent_Killer,
Here is the poop as I understand it. The 5.56x45 is but a metric designation for a .223 Rem. The difference lays in the chambering dimensions of a particular rifle. The biggest difference is that the 5.56x45 NATO spec has a longer leade (distance in barrell before encountering rifling) than in a rifle chambered for .223 (a SAAMI spec). Ammunition that is NATO spec will have a headstamp mark (circle w/ cross) indicating such. It is perfectly acceptable to fire .223 in a NATO chamber. Firing NATO in a .223 chamber can raise chamber pressures, as I understand. Hope that helps. If there is something I missed, appologies.

 

[strat81]

Owens said it pretty well. 5.56 milsurp ammo is designed to be fired in a 5.56 chamber. 5.56 chambers are a bit more generous in size and can handle higher pressures. .223 chambers are tighter and allow for better accuracy using proper ammo. For example, DPMS chambers their AR-15 clones in 5.56 except for their stainless bull-barreled models, which are .223. As an analogy for pressures, 9mm:.223 as 9mm+P:5.56.

Do NOT fire 5.56 pressure ammo in a .223 gun. Blast .223 in a 5.56 or .223 chamber all day long.

 

[Jenrick]

Just for refrence if you're rifle has a muzzle brake on it, your neighbors at the range will like it a lot less when shooting mil-surp 5.56 then commerical .223. Also try shooting 5.56 at night vs .223 it's interesting.

-Jenrick

 

[RNB65]

I have two 16" AR uppers -- one with a birdcage flash hider and one with no flash hider. The birdcage does a pretty good job of taming the flash when I shoot 5.56 milsurp. But the upper with no flash hider produces a really impressive fireball when I shoot milsurp ammo.

 

[thexrayboy]

As RNB65 has stated...visit the ammo oracle. These people do a very good job of explaining the difference between the two rounds. These differences are minor but can make for a major problem if not accounted for.

Virtually all AR versions available can safely fire 5.56 and .223. You may get differences in accuracy but they will both safely function. If you get a .223
upper that is a high end one designed for target and match work the tolerances may be such that you can damage it by using 5.56 ammo.

Shooting milsurp 5.56 out of a bolt action gun chambered for .223 is asking for trouble. You may get lucky and nothing bad happens.... doesn't mean its a good idea though.

 

[IA_farmboy]

Maybe others have, maybe the shooting ranges of America are litterd with the bodies of men who have died by firing a 762 NATO in their Winchester 308 turnbolt.

From what I have heard the 7.62NATO is identical to the .308 Winchester. There is no danger in overpressure by putting a 7.62 NATO round in a common hunting rifle chambered in .308.

 

[SpeedAKL]

Discount ammo websites are charging a hefty price premium for 5.56 NATO versus non-premium .223 commercial. Local gun dealers I've talked to haven't seen 5.56 milsurp come through in several years. Hopefully I'll find some at one of the gun shows coming up. I have a muzzle-braked AR-15 and am curious as to the supposedly impressive noise the stuff makes.

Sacrificing cheap milsurp supply so that our troops can get the best stuff they can is OK in my book tho.

 

[MMcfpd]

5.56 I know about today:

Ammoman - Swiss M193 $450/1000 rds, XM856 tracer $499/1000 rds
Wideners - Prvi Partizan M193 $283/1000 rds
Ammunition To Go - Winchester M855 $399.95/840 rds
Collector Rifle lists Federal XM193 and Prvi 55 gr. 5.56 but doesn't show availability
Ammobank Q3131 $10.71/20 rds
Cheaper Than Dirt XM855 $10.42/20 rds

If you've started to shop for ammo you've no doubt discovered that most retailers are not very conscientious about making the distinction between .223 and 5.56. I believe everything I listed above is 5.56, but I make no promises.

 

[Glockman17366]

Welcome to THR, Scott!

By the way, you bought a semi-automatic sporting rifle with a standard capacity magazine, not an assault rifle.

Assault rifles can be purchased but since they are selective fire or full automatic, assault rifles are much more expensive.

Enjoy your new semi-auto rifle!

 

[RNB65]

By the way, you bought a semi-automatic sporting rifle with a standard capacity magazine, not an assault rifle.

True! If it doesn't have a "burst" and/or "auto" setting on the selector switch, it ain't an assault rifle. It's just a semi-auto with a funky plastic stock.

 

[strat81]

True! If it doesn't have a "burst" and/or "auto" setting on the selector switch, it ain't an assault rifle. It's just a semi-auto with a funky plastic stock.

It's a homeland defense rifle. "Semi-automatic" scares the sheeple.

 

[Bartholomew Roberts]

$0.45/round for M193? Urk... I thought it was bad when I paid $0.32 per round recently for some Federal AE223.

 

[glockman19]

silent_killer,

Welcome to THR.

The Cliff notes version is you can shoot .223 out of a 5.56 barrel but not the other way around.

I shoot .223 out of my mini-14 but not 5.56. I shoot both out of my AR's

 

[silent_killer]

Well I went to the local Gun/Knife show at the flea market, and guess what? I came across some 5.56mm cartridges. I seen a few vendors with them, and they sorta looked shady, but I found one guy that had a box of M855 Penetrators. Mfg by Olin. And the butt of the casing is stamped with the NATO mark, and they are 62g.

What do you guys think? Are these the real deal, if you guys need some pictures, i will be more than happy to load some.

I also snagged some of the lake city ones from cheaper than dirt thanks to MMcfpd.

 

[glockman19]

They sound alright. As far as rounds I shoot I have Federal American Eagle, 55 grain FMJBT & JHP. I also shoot Remington UMC & Winchester Q3131. I have about 2,500 rounds of NATO stamped Lake City and som M855. I keep the M55 for special occasions & when I'll need a SD/HD/SHTF purposes. I have shot 45, 50, 55 &62 grain and prefer the 55 & 62 grain rounds.

 

[SpeedAKL]

I just picked up 55-gr .223 PMC FMJ from the local gun shop for around $6/box of 20. It's pretty solid ammo IMO at a decent price for brass.

 

[richardschennberg]

Semi-automatics guns are generally more reliable with more powerful ammunition. Since your Bushy can shoot 5.56 or .223, the 5.56 with more pressure will produce more gas to cycle the action. However, if .223 shoots well in your gun then you can use either one.