5.56 in a 223 anyone ever hear of someone blowing one up

Y

yoteblaster

Active member
I know they are chambered different but has anyone ever heard of someone having a problem with this. I am going to load some 5.56 ammo with the data Ramshot provides for TAC. It just got me thinking if anyone has ever had a problem. They sell the 5.56 stuff all over I have to believe people are shooting them in 223's.
 
Reloaded ammo wilt make any difference. The cases may be thicker which will give you less capacity by a but but not bad. I use LC and WWC mil surp brass. I use TAC also and love it with heavy bullets
 
Originally Posted By: yoteblasterI know they are chambered different but has anyone ever heard of someone having a problem with this. I am going to load some 5.56 ammo with the data Ramshot provides for TAC. It just got me thinking if anyone has ever had a problem. They sell the 5.56 stuff all over I have to believe people are shooting them in 223's.

There is no documented case of 5.56 blowing up a 223.

How are you going to load a 5.56, instead of a .223, since the cases are the same??
 
I dont believe the case is any different just the pressure limits and the gun chamber. I have a 5.56 chambered gun but I was just wandering if it had caaused a problem. I realize it isnt a good idea, just wanted to see if anyone had a problem
 
This is from Federal Ammo.


The Difference Between 223 Rem and 5.56 Military Cartridges
There is a general misperception by the shooting public that the 223 Rem and 5.56 Military cartridges are
identical – just different designations for commercial and military – and can routinely be interchanged. The
fact however is that, although somewhat similar, they are not the same.
• The cartridge casings of each have basically the same length and exterior dimensions.
• Mil Spec 5.56 ammo typically has higher velocity and chamber pressure than the 223 Rem.
• The 5.56 cartridge case may have a thicker sidewall and a thicker head - to better withstand the
stresses generated by the higher chamber pressures. This, however, reduces the powder capacity of
the case - which is of concern to the reloader.
• The 5.56mm and 223 Rem. chambers are similar but not identical. The difference is in the “Leade”.
Leade is defined as a portion of the barrel directly in front of the chamber where the rifling has been
conically removed to allow room for the seated bullet. This portion of the chamber is more commonly
known as the throat. Leade in a 223 Rem. chamber is usually .085”. In a 5.56mm chamber the leade
is typically .162”, or almost twice as much as in the 223 Rem. chamber.
• You can fire 223 Rem. cartridges in 5.56mm chambers with this longer leade, but you will generally
have a slight loss in accuracy and velocity – compared to firing the 223 round in the chamber with the
shorter leade it was designed for.
• Problems may occur when firing the higher pressure 5.56mm cartridge in a 223 chamber with its much
shorter leade. It is generally known that shortening the leade can dramatically increase chamber
pressure. In some cases, this higher pressure could result in primer pocket gas leaks, blown cartridge
case heads, and gun functioning issues.
• The 5.56mm military cartridge fired in a 223 Rem. chamber is considered by SAAMI (Small Arms and
Ammunition Manufacturers Institute) to be an unsafe ammunition combination and is listed in the
“Unsafe Arms and Ammunition Combinations” Section of the SAAMI Technical Correspondent’s
Handbook. It clearly states; “In firearms chambered for 223 Rem – do not use 5.56 Military cartridges.”
Federal Cartridge is a member of SAAMI and supports this position.
• Federal’s XM193 packaging currently has a warning that states “For use in standard 5.56 Chambers.
Do not use in non-standard 5.56 chambers.” This warning is also listed on the XM193 Product
Specification Sheet. Winchester also has a similar warning on their USA brand 5.56 ammunition
packaging: “Use only in firearms in good condition designed and chambered by firearm manufacturer
specifically for this 5.56 ammunition and so marked on the firearm.”
• It is our understanding that commercially available AR15’s and M16’s – although some are stamped 5.56
Rem on the receiver – are manufactured with .223 chambers. Our advice however should be that
it is the customer’s responsibility to know what their firearm is chambered for and choose their ammo
accordingly.
 
Originally Posted By: dan brothersisn't the only differance in the neck angle....or shoulder..?

There is no difference.

It is another "Wives tale".

The cases are the same weight, and the "leade" difference are nil.

Arguing about it will draw blood in some places, but there has NEVER been a documented problem that can be traced to using one ammo in the other gun.

Companies "warn you" cuz they are required to by their insurance companies. I just put in for new insurance, and the insurance company wants to see the warnings I will have on my cartridge boxes
frown.gif
I will simply copy what someone (bigger than I am) cuz I don't want to argue with the insurance company. It's called "Repeating the problem"

If you put a strain gauge on a barrel and fire both types of ammo - you will have the same pressures (within standard tolerances).


 
If you weigh .223 and 5.56 cases you will see they are the same.

Wikipedia:

While there is a myth that 5.56 NATO cases are thicker and hence have less capacity than commercial .223 cases, this has been shown to be false. Each brand of case and each manufacturing lot has a slightly different case capacity; 5.56 NATO and .223 commercial cases tend to have nearly identical case capacity when measured using the water test.[6] The NATO specification allows a higher chamber pressure. NATO EPVAT test barrels made for 5.56mm NATO measure chamber pressure at the case mouth, as opposed to the location used by the United States civil standards organization SAAMI. The piezoelectric sensors or transducers NATO and SAAMI use to conduct the actual pressure measurements also differ. This difference in measurement method accounts for upwards of 137.9 megapascals (20,000 psi) difference in pressure measurements. This means the NATO EPVAT maximum service pressure of 430 megapascals (62,000 psi) for 5.56mm NATO, is reduced by SAAMI to 379.21 megapascals (55,000 psi) for .223 Remington.[7] In contrast to SAAMI, the other main civil standards organization C.I.P. defines the maximum service and proof test pressures of the .223 Remington cartridge equal to the 5.56mm NATO.
 
You're right Willy. Here are some reamer dimensions and other info:

http://www.ar15barrels.com/tech.shtml

From personal experience; my wife's AR has a .223 chamber and mine is a 5.56. I can load to max mag length in mine but my rounds will jam into the lands of hers. An obviously shorter throat and higher pressure. No damage done because the rifle is built to handle it. But it is something to be aware of when loading hot.

Just check your max seating depth before assuming if it fits the mag it won't give you problems.
 
Well, its only been about a month since this was asked.

Originally Posted By: Hedge From personal experience; my wife's AR has a .223 chamber and mine is a 5.56. I can load to max mag length in mine but my rounds will jam into the lands of hers. An obviously shorter throat and higher pressure. No damage done because the rifle is built to handle it. But it is something to be aware of when loading hot.



I've seen the same happen between a Rem and Howa 243. Reamers will always be different in the through. I think there is less to this "great mystery" as it were, of 5.56 vs. 223 then most people realize. I’ve shot thousands of m193 Ball stuff in a 223 designated chamber. And, to the best of my knowledge, it wasn’t the glorious Wylde chamber or anything, just a standard .223 Rem.
 
Well they did bring out that 5.56 nuclear round uhh that name ahh nosler varmageddon.Thats it. Been shootin 5.56 in 223 for awhile no problems.
 
how many of you guys reload and mess with col it the same thing by the way when you cram the land it brings you up 7,200 psi . now 55,000 psi for a sammi 223 rem + 7,200psi for craming the lands = 62,200
and 5.56 sammi is 62,366 psi
its 166 psi diference
now if you start with 62,366 psi or a 5.56 sammi and add 7,200psi for cramming= 69,566psi
IMO you should not run over 65000 psi
a 5.56 in a gun chamberd for 223 comes in at 4,566psi over max but all guns are diferent
by the way if you gun blew up running this combo it more than the ammo that did it every gun action and barrel has to be tested befor you can get the atf aprovel to 162,500psi
or 2.5 x 65,000 and yes they do test it .
you might see a primer go or a case split at 4,566 psi

by the way you brass is the same your barrel is the same and so is your action for eather caliber


 
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Originally Posted By: 204farrhow many of you guys reload and mess with col it the same thing by the way when you cram the land it brings you up 7,200 psi . now 55,000 psi for a sammi 223 rem + 7,200psi for craming the lands = 62,200
and 5.56 sammi is 62,366 psi
its 166 psi diference
now if you start with 62,366 psi or a 5.56 sammi and add 7,200psi for cramming= 69,566psi
IMO you should not run over 65000 psi
a 5.56 in a gun chamberd for 223 comes in at 4,566psi over max but all guns are diferent
by the way if you gun blew up running this combo it more than the ammo that did it every gun action and barrel has to be tested befor you can get the atf aprovel to 162,500psi
or 2.5 x 65,000 and yes they do test it .
you might see a primer go or a case split at 4,566 psi

by the way you brass is the same your barrel is the same and so is your action for eather caliber




"... befor you can get the atf aprove"

ATF does NOT approve anything - they are a tax compliance agency.

There is NO agency that approves or disapproves pressures in guns.

In current rifles, including the M16, AR-15 family, the barrel and action if far stronger than you can imagine - 99.9999999999% of the time, it is the brass case or primer that lets go.
 
Originally Posted By: Jack RobertsJust another internet 'old wives tale'.
Many millions of rounds shot interchageably every year.
No problem.

Jack

I agree. I did watched some poor fellow get flammed to death for suggesting they were interchangeable on one of the forum loaded with "experts".
 
When I reload 5.56 brass I drop 10% and work up.I have blown primers and had to take the bolt apart to get a piece of the primer that was stopping the firing pin out.This was caused by loading the mil spec brass with the same load I was using in civilian 223 brass.If you load 5.56 and 223 brass with identical loads and shoot them over a cronograph you will see a 100+fps difference in velocity, I know as I run all my loads over my crony, this speed difference has to come from more pressure developing in the mil spec brass.
 
You can get 100 psi difference from using moly bullets,and a different proper. If your blowing primers with the same load you've got worn brass wit BO primer pockets or you reamed to much crimp out. I load All my 223 brass the same. Yes some will shoot different but never had a failure due to milspec brass loaded at regular spec
 
casecapacities.jpg



Unfortunately I cannot remember where I found this picture, so I can't credit, or cite the article.
But you can see Cat is correct. There is VERY little difference, and the military stuff is not smaller.
 
Where people might be gettin an issue is the SAW(squad automatic weapon) ammo in 5.56 is loaded hotter than AR ammo if they get ahold of that someway buts other than that been shootin 5.56 in 223 for quite awhile and no issues. I remember startin out with a cheap 700 ADL to fire it and couple of my military buds thought I was crazy until I showed them it worked. No live rounds on the range after that.
 
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