223 vs 5.56

[jwr_747]

don't want to restart the 40 year old ammo fight,but wonder why some AR-15 makers still say their rifles can only shoot 223 ammo ?? I've read all the AR-15 forum stuff,BS,theories,dreams,ect. I've known folks who shoot mil-surp 5.56 in their 223 chambered rifles,have for 40 years without any ill effects.I've seen 223 brass that has been shot in a 5.56 chambered rifle,and 5.56 brass shot in a 223 chamber,compared in an optical comparitor that looks the same.Have never seen or heard of a "blow up" from using the wrong ammo..will appreciate any answers...jwr

 

[Carolina Kalash]

the .223 remington was a civilian cartridge developed back in the 1950s, and the military 5.56mm was based on it... there is a slight, prettymuch unoticable difference in case dimensions, but the 5.56mm has a bit more umphf than the .223, so they are mostly interchangeable but some .223s dont function well if you use 5.56mm... just about all 5.56 rifles can shoot .223s all day without problem...

 

[Magog]

I can see that the 223 round is fatter in the midsection. The 5.56 is fat in the ass, and makes it yaw and break inside soft tissue causing massive cavitation and wounds.

It is evil good at killing bad guys.

I think 223 are the more accurate round, and rounds on target are 9/10's of the fire fight.

 

[C-grunt]

I can see that the 223 round is fatter in the midsection. The 5.56 is fat in the ass, and makes it yaw and break inside soft tissue causing massive cavitation and wounds.

It is evil good at killing bad guys.

I think 223 are the more accurate round, and rounds on target are 9/10's of the fire fight.

What???

223 and 5.56 are different in case dimensions. Both can and do many times shoot the same bullet.

 

[303tom]

Same !

 

[303tom]

The .223 Remington is a sporting cartridge with almost the same external dimensions as the 5.56x45mm NATO military cartridge.

 

[ugaarguy]

The .223 Remington is a sporting cartridge with almost the same external dimensions as the 5.56x45mm NATO military cartridge.

Chamber dimensions are significantly different.

 

[Sam Cade]

the .223 remington was a civilian cartridge developed back in the 1950s, and the military 5.56mm was based on it...

No.

ArmaLite engineers Jim Sullivan and Bob Fremont scaled down the AR-10 to fit the hot varmint cartridge of the day, the .222 Remington. During some preliminary military testing, it was decided that the .222 Rem wasn't quite powerful enough. Though the .222 Remington Magnum existed and had the power they were looking for, the severe shoulder angle would have prevented positive feeding in a semiauto, and so it was decided that the best solution was to lengthen the .222 Rem case. The result was the 5.56×45mm cartridge, designed by G. A. Gustafson, which Remington released commercially as the .223 Remington. This cartridge has virtually identical ballistics as the .222 Mag and, over time, the wide availability of .223 guns and ammo has lead to the demise of the .222 and .222 Mag cartridges.

 

[Sam Cade]

From the same source, The Ammo Oracle.

Dimensionally, 5.56 and .223 ammo are identical, though military 5.56 ammo is typically loaded to higher pressures and velocities than commercial ammo and may, in guns with extremely tight "match" .223 chambers, be unsafe to fire.
The chambers for .223 and 5.56 weapons are not the same either. Though the AR15
design provides an extremely strong action, high pressure signs on the brass and primers, extraction failures and cycling problems may be seen when firing hot 5.56 ammo in .223-chambered rifles. Military M16s and AR15s from Colt, Bushmaster, FN, DPMS, and some others, have the M16-spec chamber and should have no trouble firing hot 5.56 ammunition.

Military M16s have slightly more headspace and have a longer throat area, compared to the SAAMI .223 chamber spec, which was originally designed for bolt-action rifles. Commercial SAAMI-specification .223 chambers have a much shorter throat or leade and less freebore than the military chamber. Shooting 5.56 Mil-Spec ammo in a SAAMI-specification chamber can increase pressure dramatically, up to an additional 15,000 psi or more.

 

[mshootnit]

I used to reload military brass and use 223 load data. This can lead to some pretty high pressures in hunting rifles. The brass can be thicker and lead to increased pressure and/ or compressed loads.

 

[Magog]

Ok, if they are the very same, then what is it on earth that makes the 5.56 round tumble, yaw so much and rip the holly crap out of people??? And why does the simple 223 just pass on though like a 7.62x39 round?

What makes the 5.56 so ass heavy huh???

 

[Sam Cade]

Ok, if they are the very same, then what is it on earth that makes the 5.56 round tumble, yaw so much and rip the holly crap out of people???

Any spitzer FMJ bullet is going to yaw eventually if it holds together but much effort was no doubt given to increase the lethality of M855 while still achieving other design goals.

And why does the simple 223 just pass on though like a 7.62x39 round?

I don't know what you mean.
Any decent soft point commercial .223 loading will have much superior terminal effects than M855.

 

[ugaarguy]

Ok, if they are the very same, then what is it on earth that makes the 5.56 round tumble, yaw so much and rip the holly crap out of people??? And why does the simple 223 just pass on though like a 7.62x39 round?

What makes the 5.56 so rear heavy huh???

You're confusing the bullet and the cartridge. If you load .223 cases to .223 specs with the same cannelured 55gr FMJ BT that's in M193 5.56 NATO ammo you'll get very similar terminal performance.

 

[alsaqr]

Since 1968 i have been reloading US military 5.56mm brass. i weigh the cases used for my accuracy loads. US made 5.56mm military brass is not thicker or heavier than US made .223 brass. The thickest US made 5.56mm/.223 brass is Federal Glold Medal. Some Brit 5.56mm military brass is very thick. The thickest brass of all is Lapua.

http://ar15barrels.com/tech.shtml

 

[nipprdog]

wonder why some AR-15 makers still say their rifles can only shoot 223 ammo ??

Besides Remington, what other companies????

 

[Sam Cade]

Besides Remington, what other companies????

...anyone that makes an AR with a true .223 chamber.

A Tight .223 chamber plus a hot slightly oily 5.56 equals frustration and maybe danger.....


Note how Rock River lists this upper as ".223 Wylde for 5.56 & .223"?
http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=387

The Wylde chamber splits the difference between the two.

 

[Sam Cade]

On page 7 of this Document SAAMI lists 5.56 in a .223 chamber as an unsafe combination.

http://www.saami.org/specifications...1-Unsafe_Arms_and_Ammunition_Combinations.pdf

 

[alsaqr]

Since 1968 i have fired hundreds of thousands of 5.56mm rounds in .223 chambers with no ill effect. SAAMI waited for about 20 years to put out their dire warning. Why did SAAMI wait so long before issuing their "warning"? This "warning" came about after large quantities of surplus military 5.56mm ammo hit the market.

This is the same SAAMI that asked OSHA to revise their regs on manufacture, shipment and storage of small arms ammo without first consulting ammo manufacturers. When the new proposed reg came out, the ammo makers raised the roof and SAAMI started back peddling and yelled to the NRA for help.

BTW: There are at least a dozen different 5.56mm/.223 chambers. A local gunsmith told me that no manufacturer he is aware of makes a chamber to the original SAAMI .223 spec.

 

[benEzra]

Ok, if they are the very same, then what is it on earth that makes the 5.56 round tumble, yaw so much and rip the holly crap out of people??? And why does the simple 223 just pass on though like a 7.62x39 round?

It doesn't.

As others have stated, civilian .223 JHP's and SP's are superior defensive loads to 5.56x45mm M193 or M855; they are more effective while being less likely to overpenetrate. Civilian .223-marked FMJ, on the other hand, is just going to be target/plinking ammunition (e.g. Winchester white box, Tula steel-case) with bullets chosen for low cost rather than ballistics.

The difference between .223 and 5.56x45mm is primarily in chamber dimensions, not ballistics. And do be aware that some ".223 Remington" marked guns out there actually have 5.56x45mm chambers, e.g. the Ruger mini-14 (except for the Target model).

As far as 7.62x39mm goes, you described the behavior of typical 7.62x39mm M43 ball (FMJ), but not all 7.62x39mm is M43 style. There are good civilian JHP's and SP's available in the caliber, and they behave more or less like civilian .30-30 Winchester loads.

 

[Owen]

This is the same SAAMI that asked the BATFE to revise their regs on manufacture, shipment and storage of small arms ammo without first consulting ammo manufacturers. When the new proposed reg came out, the ammo makers raised the roof and SAAMI started back peddling and yelled to the NRA for help

Do you have a link to this? I find it fascinating, considering that SAAMI is an industry group for ammunition manufacturers.

 

[alsaqr]

The M193 and M855 rounds are devastating to about 150 yards when fired from a 20 inch barrel. i often kill wild hogs using the M193 round. The bullet penetrates about 5", yaws 90 degrees and fragments. Problem is that it does not perform that way every time. General Petraeus was accidently shot about 20 years ago with a 5.56mm.


http://news.bbc.co.uk/2/hi/americas/6250043.stm

Military bullet wound patterns:

http://bajaarizona.org/fklr/fklr.html

 

[alsaqr]

Do you have a link to this? I find it fascinating, considering that SAAMI is an industry group for ammunition manufacturers.

Sorry, it was not the BATFE: SAAMI asked OSHA to re-write the rules. In about 2007 we had a long, civil discussion of the proposed OSHA regs on this site. It's in the archives somewhere:

http://www.thehighroad.org/showthread.php?t=285452&page=4

To set the record straight:
1. In 2002 SAAMI petitioned OSHA to change the rules.

2. OSHA changed the rules as requested by SAAMI.

3. NSSF and SAAMI are now crying that the sky is falling. What happened to the SAAMI guy who asked for the rule change?

4. Three weeks before the comment period is due to expire, The NRA, NSSF and other groups want everyone to get up in arms at OSHA for doing what SAAMI asked them to do.

There is a lesson here: When any government agency exercises minimal authority over your industry leave well enough alone, even of their regulations are 30 years out of date.

More:

http://www.thehighroad.org/showthread.php?t=285452&page=4

It gets worse. SAAMI petitioned OSHA for the change. See page 18793 of the proposed regulations. This quote is verbatim from the proposed OSHA regulation.

"On July 29, 2002, OSHA received a
petition (the Petition) from the Institute
of Makers of Explosives (IME) and the
Sporting Arms and Ammunition
Manufacturers’ Institute (SAAMI) to
revise the standard. A copy of the
Petition can be found at Docket No.
OSHA–S031–2006–0665 (Ex. 2–1). IME
is an association of manufacturers of
high explosives and other companies
that distribute explosives or provide
other related services and the SAAMI is
an association of manufacturers of
sporting firearms, ammunition, and
related components. The Petition
claimed that § 1910.109 does not reflect
significant technological and safety
advances made by the explosives
industry since the standard was
promulgated.

 

[303tom]

You guys can argue all you want & quote this , that & what ever , I have been reloading .222 , .223/5.56 for years & like (alsaqr) says all brass is thicker and or thinner than the next. The only reason the 5.56 NATO chamber is different is to accommodate dirty ammo. The .223 & 5.56x45 are the same ! Ba Ba Ba whats word (Basically) !!!!!!!!!

 

[wally]

The two different ammos exit in large quantity and will fit in each others chambers, although function may be sub-optimal.

In today's legal liability climate where companies lose millions by serving coffee that is "too hot", do you think any manufacturer would use the chamber that had an actual safety issue? Imagine trying to defend a product liability lawsuit by blaming the shooter for using 5.56 in a .223 chamber or vice-versa.

There is a reason the really unsafe combinations (.357 in a .38 Special) were designed out by making the more powerful round not fit the weaker system.

 

[Redneck with a 40]

Isn't the 5.56x45mm loaded to a higher pressure? Isn't the chamber slightly longer on a 5.56 rifle also? I know my Mini-14 has both .223/.556 printed on the barrel.