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Can someone please tell me what if any is the difference between these identical rounds identified with different numbers?
I was asked this question today and I didn't like the answer once it came out of my mouth.
Call it ignorance, doubt or misinformation but I really want the truth.
Thanks
US of A standard measurement vs. the rest of the world and the metric system
There are some differences, but aside from the throat area of the chamber between the two it's all pretty arcane and irrelevant. Just don't use 5,56 in a rifle chambered in .223, especially regarding bolt guns. Most semi-autos are fine to swap. Colts often are marked .223 but in reality are actually 5,56, which doesn't help matters. When you start talking match rifles, there's variations inside variations. Search "Wylde chambering" or similar for an example.
My Oly Arms AR is 5.56,.223 marked receiver with a 5.56 stamped barrel so I know I'm ok but for someone who ask i'll go by what you said as I know if my life depended on it I'd shoot 5.56 in a .223 semi auto if that's all that was available. thanks
Not to beat a dead horse but is there a difference in pressure IE is 5.56 a hotter round?
I have read and heard tons of times...."if it's chambered for .223 don't shoot 5.56". Both my ARs are 5.56 so I never worried about it. I have heard the "extra" pressure in the 5.56 round theory, causing more expansion in the casing resulting in extraction problems but dont quote me :D
http://www.luckygunner.com/labs/5-56-vs-223/ .308 Winchester vs. 7.62x51mm NATO
This should answer any and all questions.
5.56 brass is thicker than .223. As a rule I have always heard ok to use .223 in a 5.56 bore but not the other way around.
I've been interchanging the ammo for 35 years and never had a problem in any weapons system.
I'm with Brian on this. Threads like this are frustrating. We go through them again and again and it never gets solved. And we continue to change 5.56 with .223 ammo in our chambers without incident. Never mind the hot stove league numbers and go shooting...Quote:
Originally Posted by Brian Dick
I don't think it will ever be a problem with ARs. There's some .223 chambered varmint bolt guns which could be a bit short in the throat for 5.56, but it seems unlikely for any factory rifle newer than 15-20 years old.
From what I gather from my limited reading the problems may start when you have a .223 chamber that has a throat that is at the shortest end of the accepted tolerances and 5.56 ammo that is at the longest.
Chambering the round when this condition exists is supposed to crimp the mouth of the case into the bullet so it can’t open properly to release the bullet significantly raising pressure possibly dangerously so.
Not so much. It's just that the throat of the .223 Rem chamber is shorter, nominally. So the bullet may either have a shorter run to the rifling or engage it upon chambering. Both will raise pressures.Quote:
Originally Posted by Rumpelhardt
Folk can't see electrons either, but they dont fret over them nearly as much. I think electrons are much more dangerous than the 5.56vs.233 thing! Watch out, your screen is glowing! So much energy flowing that the photons are all excited...
However, there are manufacturers such as Olympic who build tight-chambered ARs and specifically warn against use of 5.56 ammo and state that use will void the warranty. Who wants to void the warranty?
Bob
I've never had an AR with a warranty, they were either so old or a parts gun and had none. I did however have several Oly Frankenguns and never had problems with anything...matter of fact, the only AR thing I ever had problems with was a short barrel I assembled to a kit and it wouldn't work properly. Turned out the gas port was almost an 1/8" so it was somewhat over gassed.
"Not I!", said the cat. But unless they plaster that info on the barrel, then I'd guess they aren't too concerned. The original buyer ought to know what they're getting (a bit of a stretch, but...), however, when it shows up on the used market there is a high likihood that some 5,56 will be used. Colt marked their rifles .223 for ages even though they weren't. So it's not unreasonable to think that folk won't pay much attention to a mere caliber marking on the side of a receiver at this late date. But I do understand that 100% blanket statememts rarely work. There's probably ARs out there with custom chambers that won't shoot ANY factory 5,56 or .223 ammo.Quote:
Originally Posted by Bob Womack
Thank you. Originally wrote wondering if it was two names for the same thing. Looking at them I couldn't tell the difference. The info has been very let's say conclusively inconclusive to say the least.
Mine has 5.56 on it so I'm good and I have no .223 bolt guns so I'm good twice over.
Sometimes it's nice to see a thread that you thought was dead come back to life... Makes me think I can ask a meaningful question now and then.
Thanks again!!
I still don't think it matters.
Initially I never actually kept track of what I shot out of which AR because it was so inexpensive I never considered reloading for it. Then I got a Winchester chambered in .223 to use the brass from the AR's in. I never paid attention to whether it was 5.56 or .223 I was shooting out of it, and never noticed any signs of over pressure or anything else, that is until I bought the Remington XP 100 in .223. The first shot told me something was wrong when I had to open the bolt with a block of wood. Obvious sign of over pressure. But me being me I thought it was perhaps just the brand of ammo and pressed on with a different brand with the same result. So I tried another brand and had no sign of over pressure. I now know what I did and I will say that Remington builds a pretty tough gun to withstand what amounts to serious over pressure loads and still shoot just fine.The point being that if it says 5.56 on your barrel your good to use either. If it says .223 on your barrel....stick with .223 or carry a block of wood to open your bolt. :)
The wood block works up to a point. But I've seen more than one 700 bolt minus it's handle after the braze fails! One was in fact a .223. But in that case it was the owner's fault for getting too aggresssive with his loads. Blew the entire case head off BEFORE he proceded to further mangle the bolt. Funnily enough, the rifle was later returned to service with the same bolt after some major rework including the addition of a SAKO type extractor and a silver soldered ring replacing the ruined area surrounding the bolt face...Quote:
Originally Posted by langss
But that was the reloader's fault. I still maintain no problem.Quote:
Originally Posted by jmoore
Quote:
Originally Posted by browningautorifle
Noted!
Nor was he shooting 5,56 even though the rifle had some sort of wretched M16 magazine conversion which reduced the thickness of the feed area behind the lower locking lug. The point being that bolt handles on modern Remingtons aren't as stout as the old timey stuff.Quote:
Originally Posted by jmoore
langss was the one with the cautionary example which seems not out of the question.
I had a similar experience to the one JM describes in post 19. Mine involved a Rem. 700 Varmint in 6mm Remington and it was caused by defective factory ammo but I digress.
I also have a Howa 1500 bolt gun and 99% of the ammo I shoot in it is surplus M193 ball. I came into a 5 gallon bucket of mixed(foreign and domestic manufacture) 5.56 M193 ammo at a gun years ago and separated according to headstamp, it's about gone now but I never once had any kind of problems related to the use of 5.56 ammo in a .223 chamber.
I will after reading all this experience go with better safe then sorry.Quote:
Originally Posted by browningautorifle
Rifles marked .223 get .223. Rifles marked 5.56 get 5.56 and or .223. Rifles marked 5.56/.223 I'll use either or at this rate what I can get my hands on.
But in the case of life and death....whatever I can chamber (5.56 or .223).
Thanks again for making it interesting as usual.
Update: finally found a outdoor range (its always been there) and my son and I took our AR's , my Olympic Arms PCR-01 and his brand new Sig CM-400 and got some good quality time with our rifles. We shot both .223 and 5.56 as the preloaded mags I had were mixed and it all felt the same to us. Both AR's are 5.56 rated.
Fun was had by all. The AR is such a pleasure to shoot, so much so I bought another Olympic Arms still staying with the low budget plinker with carry handle and though these are 12 years apart I find them to be almost identical. And the price was identical too $690 ish.
I have read so many posts on various sites about the difference in .223 and 5.56 and to be honest there are so many opinions I can't count. I use .223 in my Savage FCP10 and my son shoots it in his Norinco CQ. Now I just purchased a case of what is Norinco .223 Yellow Box that we shoot in a VZ58 and the Norinco and there's a great difference in that ammo. We also use Federal .223 in both guns.
We have not had any extraction problems with any ammo in any gun and I think the Norinco yellow box is left over from a contract the Chinese had.
We did test a few different with a chronograph and the yellow box Norinco .223 is much "hotter" than any other we have used. We tried it in the Savage 10 and I won't do that again, it was IIRC a couple of hundred fps faster than the Federal and you could physically tell that when you shot it.
We bought it to use in the Norinco as that gun eats ammo and we wanted to save the better quality ammo for the Savage. The Norinco has a 10.5" barrel, the VZ a 18.5" and the Savage a 26" barrel.
One thing is there have been reports that the yellow box has a "harder" primer and some bolt guns don't like it.
Bottom line is I wouldn't use the Norinco yellow box in a quality bolt gun, just a little on the high side for load in my humble opinion. I don't think it really is .223 but possibly 5.56 no matter what is written on the box.
Thanks to all for your great post.