Is M193 safe to shoot in .223 chambers?

[UrbanHermit]

M193 was not call "5.56 NATO", nor was it called ".223" , except by some gun writers and reloading manual round histories. The correct terminology for M193 is "Cartridge, 5.56mm, M193 ball"

.223 Remington can have many different weight bullets and velocites. M193 is the standard for one particular loading of the .223 cartridge using a 55 gr. FMJ bullet, hardened primers (CCI #41 is the commercial equivalent) and a powder charge to produce 3250 fpr at 52000 psi.

From Wikipedia:

In September 1963, the .223 Remington cartridge was officially accepted and named "Cartridge, 5.56mm ball, M193." The specification includes a Remington-designed bullet and the use of IMR4475 powder which resulted in a muzzle velocity of 3,250 ft/s (991 m/s) and a chamber pressure of 52,000 psi.[5]

So it is more correct to say that Cartridge, 5.56mm Ball, M193, is one particular loading in .223 Remington.

Same with Cartridge, Ball, Caliber .30, Model of 1906; It is one particular loading in the caliber of .30-06. It is the parent loading of a group that includes 125 gr varmint loads all the way up the 220 Moose rounds.

Does this help?



Because as I have repeatedly pointed out, when the round was first adopted, the military used metric terminology for it, which is 5.56mm. 5.56 mm NATO, (or just 5.56 NATO) is a different standard. 62 gr. bullet of a particular construction, which resulted in the need to increase leade to reduce pressures. Still the same primer, and powder to achieve 3010 fps at 55000 psi.

OK, in metric (European) nomenclature, the caliber is call 5.56x45. In traditional US/English nomenclature, the caliber is called .223 Remington. The various standard rounds have different nomenclature defined by the era they were introduced. (Note Cartridge, Ball, Caliber .30, Model of 1906 is quite different from Cartridge, 5.56mm Ball, M193. [Adopted in 1963] Different times.)

The only conclusion I can draw from your post is that there is no reason why ammunition labelled "M193" cannot be used in a rifle that is stamped ".223 Remington". Is this correct? This is all I'm trying to figure out.

 

[12Bravo20]

That was what I suspected. I'm still confused though as to how M193 could be 5.56 when it predates the 5.56.

The original 223 cartridge was redesigned as 5.56 NATO in 1963 with the adoption of the M16 by the US military. The 223 was released as a civilian commercial cartridge in 1964. Pretty much all source will say the same.

 

[243winxb]

https://discover.dtic.mil/ You can search for. "M193 Ball" at link.

 

[UrbanHermit]

https://discover.dtic.mil/ You can search for. "M193 Ball" at link.

So, I just tried that, and found nothing that answers my question. I guess I'll just have to wait for Ruger to get back to me, whenever they get around to it. They'll probably give me a vaguely worded lawyer answer.

 

[12Bravo20]

The only conclusion I can draw from your post is that there is no reason why ammunition labelled "M193" cannot be used in a rifle that is stamped ".223 Remington". Is this correct? This is all I'm trying to figure out.

Again if the ammo is true M193 loaded to military specs, then you should not fire it in a tighter 223 chamber. Again most manufacturers know that most people will go out and buy the cheaper military surplus M193 ammo to shoot out of their 223 chambered rifles and they now make the 223 chambers on the loose side of spec to allow for this. Otherwise "Bubba Fudd" would sue the manufacturer even though he used military M193 ammo in a 223 chambered rifle.

And yes at least two of us have had issues with the H&R Handi-Rifle while shooting mil spec M193 in them. the higher pressure caused the action to pop open and NO there was nothing wrong with either rifle.

 

[entropy]

The only conclusion I can draw from your post is that there is no reason why ammunition labelled "M193" cannot be used in a rifle that is stamped ".223 Remington". Is this correct? This is all I'm trying to figure out.

Well, as 12Bravo2o posted, and I concurred, having had the same thing happen, I would not shoot M193 ball in an H&R Handi-Rifle. I have fired them in several Savage Axis rifles, which produced flattened primers, but extracted and ejected. These and AR are the only rifles I've fired it in.

If you're firing them in a Ruger bolt or a Mini-14 you should be fine. But, yes Ruger will give you weasel word of a legal dialect.

 

[UrbanHermit]

The original 223 cartridge was redesigned as 5.56 NATO in 1963 with the adoption of the M16 by the US military. The 223 was released as a civilian commercial cartridge in 1964. Pretty much all source will say the same.

But 5.56 NATO was invented in the late 70s. That's what I just read. I have not read any authoritative information as of yet that states that M193 is a different cartridge from .223 Remington or is loaded to higher pressure, longer COL, or has any other feature that would distinguish it from .223 or render it unsafe to shoot in rifles chambered in .223.

 

[12Bravo20]

I'm getting a Ruger Bolt Action that is advertised as being chambered in .223

The only way to fin out with 100% certainty is for you to do a cast of the chamber and measure it to see if it is a true 223 chamber, 223 Wylde chamber or 5.56 chamber, or somewhere in between.

 

[12Bravo20]

But 5.56 NATO was invented in the late 70s. That's what I just read. I have not read any authoritative information as of yet that states that M193 is a different cartridge from .223 Remington or is loaded to higher pressure, longer COL, or has any other feature that would distinguish it from .223 or render it unsafe to shoot in rifles chambered in .223.

Reread all of the links that we have provided. The original 5.56 M193 came out in 1963 when the US Military adopted the M16 rifle. The 5.56 NATO M855 came out later when the 62 grain bullet was standardized for use by all NATO countries.

 

[UrbanHermit]

Again if the ammo is true M193 loaded to military specs, then you should not fire it in a tighter 223 chamber. Again most manufacturers know that most people will go out and buy the cheaper military surplus M193 ammo to shoot out of their 223 chambered rifles and they now make the 223 chambers on the loose side of spec to allow for this. Otherwise "Bubba Fudd" would sue the manufacturer even though he used military M193 ammo in a 223 chambered rifle.

And yes at least two of us have had issues with the H&R Handi-Rifle while shooting mil spec M193 in them. the higher pressure caused the action to pop open and NO there was nothing wrong with either rifle.

But the military specs suggest that M193 is identical to .223 Remington. I have not seen anything stating conclusively that M193 is hotter than .223, or that M193 is 5.56 NATO. Several ammo companies are putting out 55 grain ammo with .223 ballistics and specs that say "5.56" on the box, but do not say "NATO".

 

[entropy]

Knowing Ruger, they probably say don't shoot 5.56 ammo in their rifles and then cut the chambers to 5.56 standards anyway.

 

[UrbanHermit]

Reread all of the links that we have provided. The original 5.56 M193 came out in 1963 when the US Military adopted the M16 rifle. The 5.56 NATO M855 came out later when the 62 grain bullet was standardized for use by all NATO countries.

So then it is safe to shoot M193 in .223 rifles. Correct?

 

[UrbanHermit]

Knowing Ruger, they probably say don't shoot 5.56 ammo in their rifles and then cut the chambers to 5.56 standards anyway.

Yes, most likely. And to make matters worse, nobody seems to know if M193 is 5.56.

 

[12Bravo20]

But the military specs suggest that M193 is identical to .223 Remington. I have not seen anything stating conclusively that M193 is hotter than .223, or that M193 is 5.56 NATO. Several ammo companies are putting out 55 grain ammo with .223 ballistics and specs that say "5.56" on the box, but do not say "NATO".

And that right there is the difference. 5.56x45 is the metric designation for .223. And if labeled correctly by the manufacturers it should say XM193 or XM855 instead of M193 or M855. And yes all military 5.56 ammo accepted for service use by all NATO countries will also have the NATO symbol on the case and should NOT be fshot in a gun with a 223 chamber.

 

[entropy]

So then it is safe to shoot M193 in .223 rifles. Correct?

NOT NECESSARILY. As 12Bravo20 suggests, get a chamber cast done if you are in doubt.

Yes, most likely. And to make matters worse, nobody seems to know if M193 is 5.56.

I know at least two people in this thread who know the answer.

 

[12Bravo20]

Yes M193 is 5.56 ammo and loaded to the hotter 5.56 specs. Anything labeled as XM193 is loaded to 223 specs.

 

[UrbanHermit]

The only way to fin out with 100% certainty is for you to do a cast of the chamber and measure it to see if it is a true 223 chamber, 223 Wylde chamber or 5.56 chamber, or somewhere in between.

I think there are gauges too.

 

[243winxb]

Midwayusa has listed many 223 & 5.56 Nato ammo types. View attachment 1023522


More old info https://www.accurateshooter.com/cartridge-guides/223rem/

 

[UrbanHermit]

Yes M193 is 5.56 ammo and loaded to the hotter 5.56 specs. Anything labeled as XM193 is loaded to 223 specs.

Do you have any sources for any of that? I suspect that you're correct but I want to be sure.

 

[UrbanHermit]

Midwayusa has listed many 223 & 5.56 Nato ammo types. View attachment 1023522

Many of the boxes themselves do not say "NATO" anywhere on them. I have a few in my possession.

 

[UrbanHermit]

NOT NECESSARILY. As 12Bravo20 suggests, get a chamber cast done if you are in doubt.



I know at least two people in this thread who know the answer.

But why would the chamber matter if M193 is .223 spec ammo as is implied by everything I've read? If it's. 223 then you can use it in any chamber.

 

[12Bravo20]

I think there are gauges too.

Most gauges are for checking headspace only, they are labeled "GO" or NOGO", they will not tell you what the chamber for. And if you stick a 5.56 GO gauge into a 223 chamber, it will false tell you that the gun fails the headspace test.

Do you have any sources for any of that? I suspect that you're correct but I want to be sure.

Read all of the different links that we have provided you. Most sources will tell you that anything marked as M193 is a true mil spec 5.56 round and anything marked as XM193 is loaded to 223 pressures.

 

[12Bravo20]

But why would the chamber matter if M193 is .223 spec ammo as is implied by everything I've read? If it's. 223 then you can use it in any chamber.

Again M193 is NOT the same as 223 and is loaded hotter to military specs. XM193 is loaded to 223 specs. If the manufacturers are not labeling their ammo correctly then they are opening themselves to lawsuits.

 

[UrbanHermit]

Most gauges are for checking headspace only, they are labeled "GO" or NOGO", they will not tell you what the chamber for. And if you stick a 5.56 GO gauge into a 223 chamber, it will false tell you that the gun fails the headspace test.



Read all of the different links that we have provided you. Most sources will tell you that anything marked as M193 is a true mil spec 5.56 round and anything marked as XM193 is loaded to 223 pressures.

Of course it's "mil spec". It's a military designation for .223. Which source states that it is loaded to higher pressure than .223? I know that 5.56 NATO is higher pressure, but that was invented 17 years after the M193. You can't automatically assume it's higher pressure than .223 just because it's 5.56 if it literally isn't 5.56.

 

[entropy]

But why would the chamber matter if M193 is .223 spec ammo as is implied by everything I've read? If it's. 223 then you can use it in any chamber.

Because then you would know which chamber your Ruger truly has.
As I said before, it wouldn't surprise me if Ruger stamped .223 Remington on the barrel, but cut the chamber to 5.56 NATO specs anyway as a CYA move.

I suggest you shoot only commercially labelled .223 Remington. This will remove all doubt.