5.56 in a. 223?

M

MagDiddy

New member
Some hand loaders have told me that I can shoot 5.56 in my . 223. Most info I see says not to. I don't want to damage my rifle or void its' warranty. Any opinions are appreciated.
 
The best way to preserve your warranty is to use the product in accord with its intended usage as published by the manufacturer.

Pretty simple, really...

Bayou
 
Just remember it's a big argument to ask this question. For simplicity just shoot the cartridge your rifle is stamped for.
 
Seems like the correct way to proceed. That's what I figured and what most experts say. No need for 5.56 anyway. Thanks.
 
Many of us used both interchangeably, without incident, LONG before the internet was invented and the self proclaimed experts were able to tell us it was wrong. Probably a loaded question to ask on here.

Check the owners manual and follow their advice.
 
I've been shooting them interchangeably for about 40 years with no issues. Realistically the worst thing likely to happen is a semi-auto rifle set up for 223 might not cycle reliably with full power 5.56. The only semi-auto 223 rifle I'm aware of are the older Ruger Mini-14's. All modern semi-autos are set up for both 5.56 and 223. In a bolt rifle you'll never have any problems.

The fact that 223/5.56 and 308/7.62 use different military and commercial designations, and slightly different power levels causes a lot of confusion. The reality is that ALL cartridges are loaded to different power levels. The 30-06 is a perfect example but to a lesser extent this is true with every cartridge made.

There are at least 5 different power levels 30-06 can be loaded to. WW-1 loads pushed a 150 gr bullet to 2700 fps. By WW-2 that was up to 2800 fps. Modern factory loads are now typically 2900 fps with some as much as 3000 fps. Some handloads will safely reach 3100 fps. But not all of those loads will work in every rifle.

But even with that wide range of power levels we only have one name for 30-06 and no one worries much about it. You are in the real world far more likely to run into a dangerous situation loading the wrong 30-06 ammo into the wrong rifle than you are by loading 5.56 in a 223 rifle.

The difference between different 45-70 loads is even more dramatic.
 
jmr40 hit the nail on the head here. It is really not as complicated as so many people believe. I am not sure I would load to 5.56 pressure in a semi auto in 223, but I have done so in bolt rifles for a long time and never had any trouble what so ever.
 
The reason you can not shoot 5.56 in your 223 is that 5.56 brass is considered military brass and is loaded at higher pressures. The internal dimensions in a .223 chamber are smaller and the chamber in a 5.56 are larger. The freebore in a .223 is about .025 and in the 5.56 it is twice the length, thus allowing the 5.56 chamber to handle the higher pressures. You can shoot 223 in a 5.56 rifle but not the other way around.
 
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...unless your gun is running at the ragged edge of safe pressure for it's material and has a precisely in-spec .223 rem chamber, it will probably not be an issue.

There are technical differences, but I've never seen a firearm fail due to this.
 
Attention: ms6852

5.56 brass is considered military brass and is thicker than regular commercial 223 brass. The internal dimensions are smaller on the 5.56 brass which causes higher pressures than the 223
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FALSE! Are you quoting misinformation? Or, is that your personal theory, and interpretation? That goes for 7.62 LC, but is false, unsupported, often repeated, myth for 5.56. I would like to see your factual reference for that claim.
There are tables of 223/5.56 brass comparison here:
https://www.accurateshooter.com/cartridge-guides/223rem/
FYI. LC 5.56 for 2 different years were among the highest H2O capacity. Opposite of your statement.
https://www.luckygunner.com/labs/5-56-vs-223/
[5.56 chambers] have longer leades [True]
and are able to with stand the preasures the .223 have shorter leades which will increase the pressures in your chamber possibly causing catastrophic damage to you and firearm.
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Conjecture, interpretation, opinion.
You can shoot 223 in a 5.56 rifle but not the other way around.
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Actually you can, and many people do so.
I do agree everyone should know their firearms. It is a personal choice whether you want to. The sky is not falling.
 
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ms6852 said:
The reason you can not shoot 5.56 in your 223 is that 5.56 brass is considered military brass and is thicker than regular commercial 223 brass. The internal dimensions are smaller on the 5.56 brass which causes higher pressures than the 223.
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This assumes the components and assembly details are the same in each cartridge. That's not happening. Same thing with the 7.62 NATO vs. the 308 Win.
 
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223 is ok in 5.56.
5.56 is NOT ok in 223.
5.56 and 223 are ok in 223 wylde.

SAAMI, the people that spec the cartridges, says 5.56 in a 223 is unsafe, as Bart B. noted.

People will debate the specs and designs as I'm sure you can already see above. Follow what SAAMI says, anything else is at your own, and your guns risk.
 
Page 8 from SAAMI shows it is not safe.
https://saami.org/technical-information/unsafe-firearm-ammunition-combinations/

Just because one drives a car with bald tires does not mean they won't blow up, it happens with new tires.

So why take a chance this will not happen with your rifle, simply because someone from the internet you may not know says they do it all the time. The moon is made out of cheese.

Rifles are manufactured to withstand pressures beyond what a certain round will produce but when you shoot a round that is loaded with higher pressures eventually that rifle made for the round loaded with the lower pressures may weaken its integral structure with continuous repetitive firing of over pressure rounds. It did its job in protecting you from an accidental shooting of over pressured round but not for sustained shooting. It's like bending a wire, you may bend it a few times but eventually it will break.

It is your face and your life so it is your choice what you do.
 
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Which .223 rifle? If it's a Mini-14, you can give Ruger your serial # and they'll tell you if it is safe to fire 5.56, even though the receiver is marked ".223". IIRC, Ruger often says "safe".
 
I don't want to damage my rifle or void its' warranty.
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Best way to not void the warranty is to not shoot it.;) I don't know of any of the commercial manufacturers that will honor a warranty if you use reloads. I believe the principal danger is doing reloads near max charges without knowing what the possible reduced case capacity can do to your pressure--particularly if there's a risk of bullet set-back when chambered.
 
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