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.223 Remington vs. 5.56 NATO: What You Don’t Know Could Hurt You
Bearing Arms ^ | 13 Feb, 2015 | Bob Owens

Posted on 10/29/2016 5:17:13 PM PDT by MtnClimber

Is firing a 5.56 NATO cartridge in your .223 Remington chambered AR15 dangerous? Or do Internet forum-ninjas and ammunition companies selling you commercial ammo instead of surplus overstate the dangers? Believe it or not, a real danger exists, and some gun owners who think they are doing the right thing may not be safe.

The Cartridges

The .223 Remington and 5.56×45 NATO cartridges are very similar, and externally appear the same. But there are some differences that lie beneath the surface.

The 5.56 case has thicker walls to handle higher pressures, meaning the interior volume of the case is smaller than that of a .223. This will alter the loading data used when reloading 5.56 brass to .223 specs.

Some 5.56 loads have a slightly longer overall length than commercial .223 loads.

The Chambers

The significant difference between the .223 Rem and 5.56 NATO lies in the rifles, rather than the cartridges themselves. Both the .223 and 5.56 rounds will chamber in rifles designed for either cartridge, but the critical component, leade, will be different in each rifle.

The leade is the area of the barrel in front of the chamber prior to where the rifling begins. This is where the loaded bullet is located when a cartridge is chambered. The leade is frequently called the “throat.”

On a .223 Remington spec rifle, the leade will be 0.085”. This is the standard described by the Sporting Arms and Ammunition Manufacturers’ Institute, Inc. (SAAMI). The leade in a 5.56 NATO spec rifle is 0.162”, or almost double the leade of the .223 rifle.

(Excerpt) Read more at bearingarms.com ...


TOPICS: Outdoors
KEYWORDS: ammunition; banglist
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1 posted on 10/29/2016 5:17:13 PM PDT by MtnClimber
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To: MtnClimber

I have heard of possible issues for years, but never an explanation.


2 posted on 10/29/2016 5:18:03 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: MtnClimber; mylife; Joe Brower; MaxMax; Randy Larsen; waterhill; Envisioning; AZ .44 MAG; umgud; ...
.223 Remington vs. 5.56 NATO

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Please FReepmail me to be added to or deleted from this ping list.

3 posted on 10/29/2016 5:25:06 PM PDT by PROCON ("LOCK HER UP, LOCK HER UP!")
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To: MtnClimber

Dono, but if you get touched in the forehead with a .17 your future is a mess.


4 posted on 10/29/2016 5:26:44 PM PDT by Bogie
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To: MtnClimber

My newly purchased M-4 COLT has 5.56MM on the box, and the serial number. The same COLT rifle has .223 stamped on the rifle and the same serial number.

I have fired BOTH cartridges in a RUGER Mini-14 and other rifles with no problems.


5 posted on 10/29/2016 5:27:40 PM PDT by Ruy Dias de Bivar (Evil women. Jezebel, Athaliah, Livia Drusilla, Messalina, Lucrezia Borgia, Hillary Clinton)
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To: MtnClimber

I specifically bought a 5.56 to avoid the potential issues of buying .223 and using both ammo. So far I have strictly used 5.56 ammo in my Armalite Eagle-15.


6 posted on 10/29/2016 5:29:01 PM PDT by Reno89519 (Trump/Pence or Crooked Hillary & Kreepy, The Pedo Klown)
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To: MtnClimber
Gimme a break. .223 is imperial measurement while 5.56 is metric measurement for the same cartridge.
Good grief
7 posted on 10/29/2016 5:29:04 PM PDT by Fiddlstix (Warning! This Is A Subliminal Tagline! Read it at your own risk!(Presented by TagLines R US))
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To: PROCON

With reloads I have seen signs of excessive pressure with loads that should be well below mazimum and now that I think of it it was military 5.56 brass.


8 posted on 10/29/2016 5:29:25 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: Reno89519

Me too.


9 posted on 10/29/2016 5:33:00 PM PDT by Cobra64 (Common sense isn't common any more.)
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To: Fiddlstix
Tsk, tsk, you didn't read the article, did you?

How about the leade?

10 posted on 10/29/2016 5:33:38 PM PDT by PROCON ("LOCK HER UP, LOCK HER UP!")
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To: Fiddlstix

Do research on the case dimensions. The geometry is different.


11 posted on 10/29/2016 5:33:58 PM PDT by Cobra64 (Common sense isn't common any more.)
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To: Fiddlstix

Wrong. Slightly higher chamber pressure for 5.56 vs .223 ammo. Results in about 150-200 fps difference. Not a huge difference but some and specifications behind that nomenclature.


12 posted on 10/29/2016 5:34:58 PM PDT by wgmalabama
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To: MtnClimber

Wylde about the potential ...... :o)


13 posted on 10/29/2016 5:35:17 PM PDT by Squantos (Be polite, be professional, but have a plan to kill everyone you meet ...)
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To: Fiddlstix

The case thickness and bullet seating dimensions are explained in the article. If you don’t reload then it may not make sense.


14 posted on 10/29/2016 5:36:41 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: wgmalabama

Yes, the thicker case for the 5.56 means pressure will be higher than a similar charge in .223. If you reload a max .223 charge in a 5.56 the pressure will high enough that you may get a case rupture.


15 posted on 10/29/2016 5:39:48 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: MtnClimber

That’s cool;) I only buy 5.56mm for target practice, but for personal defense I have 30-round mag’s (27 rounds) filled with .223 hollow points.


16 posted on 10/29/2016 5:40:02 PM PDT by Jumper
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To: MtnClimber

When reloading most sort out the military brass and the Commercial brass for the same capacity reason. Some go as far to weigh the brass for consistent loads.


17 posted on 10/29/2016 5:40:48 PM PDT by mountainlion (Live well for those that did not make it back.)
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To: MtnClimber
As if the confusion regarding the .223 vs 5.56 chambers wasn’t enough, there is a third possibility in the mix, that is being used by at least one major manufacturer. The .223 Wylde chamber is a modified SAAMI-spec .223 chamber that allows for the safe use of 5.56 NATO rounds, but maintains tighter tolerances for better accuracy.

The Armalite Eagle-15 I picked up last June is chambered in .223 Wylde. That's what sold me on it.


18 posted on 10/29/2016 5:43:18 PM PDT by Drew68
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To: Ruy Dias de Bivar

The Mini 14 is chambered for 5.56 which means you can use .223 also.If it was chambered in. 223 it would be a no bo to fire a 5.56 in it.


19 posted on 10/29/2016 5:45:21 PM PDT by Renegade
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To: MtnClimber

If the military brass has less internal capacity, it will take less of a given powder to reach a specific pressure than commercial .223. Chamber specs vary a bit between 5.56 and .223, and even the Wylde chamber. The cartridges, loaded to their respective pressures are interchangeable, the minute differences in chamber specs for reliability.


20 posted on 10/29/2016 5:46:31 PM PDT by Quickgun (I got here kicking,screaming and covered in someone else's blood. I can go out that way if I have to)
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