5.56 in a .223 rifle

jcatony

Has anyone here used 5.56 in their .223 rifle? Local dealer has started selling 5.56 and says he has had no complaints. Another dealer told me that was bad for the rifle. I own a Brno 527 myself.

johngalway

Military rounds would be loaded for a higher pressure than your rifle is ment for as far as I know. Know of people who have used them in the UK, I wouldn't.

foxshooter243

jcatony wrote: »

Has anyone here used 5.56 in their .223 rifle? Local dealer has started selling 5.56 and says he has had no complaints. Another dealer told me that was bad for the rifle. I own a Brno 527 myself.

This is one of those questions that never really has a final answer, the fact is that every year millions of rounds of 5.56 mill spec ammo is fired through 223 sammi spec chambers, in real terms the two are interchangeable, but the mill spec ammo is operating at 60.000 c.u.p whilst 223 sammi spec normally operates at 54,000 c.u.p. the reason for the different terminology is that in the 1950 s the US millitary adopted the
metric system of measurement and uses metric measurements to describe ammo, the commercial manufacturer stays with the british imperial system.
dimensionally both bullets are the same but the difference in operating pressure would mean that if you used the mill surp in a rifle with a really tight match 223 chamber it could be unsafe.but who in their right mind would purchase a rifle with a match chamber and the use cheap mill surp ammo, it would be defeating the purpose.
there is also the difference in chambers between a 223 sammi spec and a 5.56 nato spec- commercial sammi spec 223 chambers { yours} has a much shorter throat or leade and less freebore than the 5.56 nato.
the 5.56 nato chambers are sloppy to allow the rifles to work when dirty.

so to cut a long story short , theres no problem using mill spec ammo in a "factory" chamber, but youll find you wont get the same accuracy as the commercially made "good" ammo, also the brass has a crimp on the primer hole so its not worth saving to reload, another point to remember is that the later runs of mill spec are using a heavier bullet that wont stabilise in a 14 twist, but its one of those old should you or shouldnt you type questions, in my opinion if you want to use then use it.

ive used it in a sako 75 223 and the accuracy was crap!:eek::eek:

Grizzly 45

DO NOT DO THIS!!!!! Unless you are shooting a gun specifically marked for 5.56 NATO!!!
Foxshooter is correct on all the tech details in his previous post RE the throat dimensions and the SAMMI Vs US Milspec etc.
There are indeed some rifles that are chamberd to take both calibres.
BUT most gun manufactures advise against it to the point of it invalidating your warranty.
Check out www.fulton-armoury.com for a good definitive article on this 223 vs 5.56 NATO. It is ok to shoot 223 in a 5.56.BUT not the other way round. I'm sure most guns will handle the difference.But why risk it??
Later
After reading Jctony's post again.It is possible that the dealer is selling a European brand of ammo marked 5.56 METRIC.. European ammo makers don't mark their ammo in Imperial measurements. So long as it isnt 5.56 NATO,it should be well OK.

Jonty

If you look on any box of ammo it says "only use in rifles with similar markings" ie .308 in .308 only.

I wouldn't bother with it.

foxshooter243

I know what youre sayin lads but the fact of the matter is that millions of rounds of mill surp are used in 223 sammi specs every year ,cos the factory chamber tolerances allow it-and will always be the case cos its down to cheap ammo-but normally any discerning rifleman will soon change after seeing the accuracy anyway, last weekend i was shooting a sako 75 in 308 at targets-the first load was a worked up load and the five
bullets made the one hole at 100 yrds, we then tryed radway green mill surp in 308-next five showed a 2 inch group
but the difference was that 20 rds of radway green in 308 was costing 5 euro per 20:eek::eek:.

johngalway

My last post in this thread will be this (not critisizing anyone by the way). Err on the side of caution and don't use it

foxshooter243

johngalway wrote: »

My last post in this thread will be this (not critisizing anyone by the way). Err on the side of caution and don't use it

Good advice john , but its one of the old perrenial questions that keeps popping its head up ,;)

peter-pantslez

i heard somewhere that you can use a .223 in a 5.56 rifle but neve use a 5.56 in a .223 rifle because they contain a higher charge and you'll wreck your rifle!!!!

meathstevie

I'd go with JohnGalway on this one. Don't find out through a costly mishap or worse, a nasty injury.

To the best of my knowledge Peter-Pantslez is right about using .223 civilian in a 5.56 nato chambered rifle, it should swallow and fire it without any problem. The other way around I believe can be a bit troublesome. American Eagle do good .223 ammo for a very reasonable price and if it's zeroing and target you want to do Remington does cheap enough .223 ammo in FMJ as well.

jcatony

Many thanks for the advice lads. I only bought one box of that ammo. The box was marked "5.56 Ball" safe to say it is military. Don't think i'll risk it.
One more thing, has anyone here used Barnaul ammo?

meathstevie

5.56 Ball is military stuff allright. In normal English it refers to what you call an ordinary bullet as compared to tracer, armour piercing etc... . If you Google Barnaul reviews you'll get a very mixed bag but every review also mentions the fact that it's cheap ( Russian I believe ). If your rifle likes it it should be ok.

fathersymes

Bought some 5.56 Nato last year, four misfires before one fired, then another few misfires. Unnerving those misfires, so disposed of the box, useless, I think they were '70's surplus from the serial no..

foxshooter243

fathersymes wrote: »

Bought some 5.56 Nato last year, four misfires before one fired, then another few misfires. Unnerving those misfires, so disposed of the box, useless, I think they were '70's surplus from the serial no..

they have hard primers in them and misfires with them is common.;)

fathersymes

foxshooter243 wrote: »

they have hard primers in them and misfires with them is common.;)

Does this mean military firing pins hit harder or they are designed that way for more stabilty??

Manic Moran

Jonty wrote: »

If you look on any box of ammo it says "only use in rifles with similar markings" ie .308 in .308 only.

I wouldn't bother with it.

When I was putting together my FAL, I had to choose whether to use the headspace gauge for .308 or 7.62 NATO. I went with 7.62 NATO, but have generally only been able to find .308 ammunition around these parts.

So far so good.

However, I will not shoot 5.56 out of a .223 chamber, with one exception: Some rifles manufactured in the US are marked .223 even though they're built for 5.56 NATO specs. (The latest MSAR 556s come to mind) The reason is apparently something to do with the laws regarding the manufacture of military-calibre weapons.

NTM

foxshooter243

fathersymes wrote: »

Does this mean military firing pins hit harder or they are designed that way for more stabilty??

The reason that the millitary ammo uses hard primers is to prevent slam fires and what they call "out of battery" detonation, thats when the round goes off before its properly chambered.millitary firearms have a freefloating firing pin rather than a spring loaded one.in a semi auto action tha energy of the fired round forces the bolt and the bolt carrier back ejecting the spent round and a spring forces the bolt forward and brings with it a fresh round , then when the face of the bolt hits the head of the chamber the firing pin is carried on due to its inertia until it stops on the primer, and sometimes this can be enough to cause the slam fire. and in battle conditions where dirt is a problem the problem gets worse due to dirt getting in to the channel in firing pin.so to overcome this problem they use very hard primers so when you consider that the millitary primer is hard to begin with and that primers will harden with age as well, then when you pop off down to the gunshop and come back with some mill surp that
could have been stored badly for 10 or 20 years then dont be suprised when they fail to fire on every 7th or 8th shot.