WHOA! Is .223 really different from 5.56?

[Lavan]

Clayfish warned me in another thread. I have been using GI ball in the Savage varminter with no ill effect. What is the "danger?" I thought they were the same. I've also sent a few thousand through my Mini-14.

What's the scoop?



Edited to add that I am thinking of getting another .223 to use up more ammo. Are the modern guns like Remington or Tikka going to have troubles with 5.56 ammo? Seems unlikely from such a small case in such monstrous actions.

But........?????????

 

[cuate]

Holy Mackerel, Sapphire!

Best I run to the safe and tell my Ruger Mod 77, MkII and the Mini 14 Ranch rifle, and the Thompson Center all in .223 that they have been eating wild ammo for several years!

Seriously, if anyone really has a valid slant on shooting the 5.56 GI in civvie guns, please expound, I am listening. Never too old to listen.........

 

[Dave R]

Ummmm, I shoot 5.56 NATO in my .223 rifle all the time.

Speer No. 13 reloading manual treats them essentially the same, with a note to watch out for reduced case capacity in the thicker milsurp brass...

 

[Lycanthrope]

.223 and 5.56 Ammunition have the exact same dimensions, but .223 and 5.56 chambers differ. Due to the larger chamber of 5.56, military ammo is often loaded hotter as the larger 5.56 chamber will keep the pressure on the safe side. Firing hot 5.56 ammo in a tight .223 chambered gun can up pressures 15,000psi...or more. This is likely not a problem in most bolt guns....which are strong.....but shooting 5.56 ammo out of a match chambered .223 AR15 could be a very bad thing.

Here's a lot more on the subject.

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

 

[combatpreacher]

5.56 also has thicker brass in some areas of the case (at least this is my understanding)...to help it withstand the extractors on some automatic or "machine" guns.

I hear the problem comes about when you try to handload the military brass with a maximum charge for the 223...less space inside the case = more pressure...maybe even too much.

Just what i have heard though...I also shoot both kinds and have never had a problem.

 

[buckster]

Wylde vs 223/nato

RRA offers these two chambers; which one. Is the Wylde just a more precision chamber, can you use any ammo? Varmit A4 18. Hurry, they're on the phone.

 

[Lycanthrope]

Wylde is tighter than 5.56 chambers but safe to shoot both 5.56 and .223 ammo!

GO!

 

[silicon wolverine]

This issue likely originated with bushmaster. They are the first ones i can see that list an issue with 5.56mm vs. .223 chambers. Bushie lists thier rifles as having .223 or 5.56 chambers in the catalouge. At the back they have a half page article on this and which you should choose. They state that the 5.56 chamber is .002 longer than a standaer .223 chamber. Enough to jump pressures into the dangerous territory if you use 5.56 in a .223 chamerbs gun. that siad, my ruger ranch rifle is chamberd in .223, and after speaking with a ruger factory rep he siad this difference would only matter in highly tuned match grade guns and told me not to worry about it. Ive shot thousands of rounds of 5.56 in my mini with no ill effects for me or the rifle. Unless you shoot benchrest auto its a moot issue.

SW

 

[Nicotine]

this thread should probably be made a sticky, or one like it, since it seems like a max of 1 month will go by before someone asks this same question.

 

[Death from Afar]

+ 1 on Sticky

SAAMI did issue a warning on this a wee while back, so it should be taken seriously. I doubt it does make a difference but still....

As an aside I use military brass in my .223 Ackley . The thicker annealed neck makes fire forming far easier.

 

[kingudaroad]

this thread should probably be made a sticky, or one like it, since it seems like a max of 1 month will go by before someone asks this same question.

Isn't that what the search function is for?

No need to be sticky happy.