Difference between .223 and 5.56
- Thread starter pindar
- Start date
.223 is ok in a rifle chambered for 5.56, but the reverse is not true, or atleast in most cases not advisable.
5.56 produces greater pressures and inturn more heat...if the firearm is not designed to handel it it could be damaged.
5.56 produces greater pressures and inturn more heat...if the firearm is not designed to handel it it could be damaged.
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The two terms are used interchangeably these days. Basically, saying .223 is politically correct for firearms and ammunition manufacturers, while 5.56 is scary military lingo, a cartridge not to be trusted with us lowly tax peons and to be prevented from cross border export.
There's actually reports that many munition manufacturers are making the same cartridges and putting them in different boxes depending on the market. 5.56 for military and .223 for hunters and plinkers.
That said, at one time there was a difference, but these days it's become irrelevant.
There's actually reports that many munition manufacturers are making the same cartridges and putting them in different boxes depending on the market. 5.56 for military and .223 for hunters and plinkers.
That said, at one time there was a difference, but these days it's become irrelevant.
- Location
- Pt. Hawkesbury, NS
lol.. 5.56mm Yerp... C7 and C9 Ammo... trust me. Military Jargon thats all, its still your standard .223 where as your C6 Machine Gun would fire 7.62mm AK Calibre
- Location
- Ottawa, Ontario
no the C6 fires 7.62 x 51 nato not the 7.62x39 soviet
"...more heat..." The heat generated is irrelevant.
Some will say the 5.56 case is a bit longer. Before there was an Internet, the cartridges were identical. Nothing has changed.
"...not the 7.62x39 Soviet..." Never has and never will either.
Some will say the 5.56 case is a bit longer. Before there was an Internet, the cartridges were identical. Nothing has changed.
"...not the 7.62x39 Soviet..." Never has and never will either.
http://ammo.ar15.com/ammo/
This page may answer some of your questions. FAQ's are on the right of page.
SW
This page may answer some of your questions. FAQ's are on the right of page.
SW
In general, commerical 223 from the US is at least 100 to 250 fps slower than it's military counterpart.
Stole this from wiki - it is actually quite good and put everything to perspective:
While the 5.56mm NATO and .223 Remington cartridges and chamberings are very similar, they are not identical.
Military cases are generally made from thicker brass than commercial cases; this reduces the powder capacity (an important consideration for handloaders[6]), and 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.
The 5.56mm NATO chambering, known as a NATO or mil-spec chamber, has a longer leade, which is the distance between the mouth of the cartridge and the point at which the rifling engages the bullet. The .223 Remington chambering, known as SAAMI chamber, is allowed to have a shorter leade, and is only required to be proof tested to the lower SAAMI chamber pressure. To address these issues, various proprietary chambers exist, such as the Wylde chamber (Rock River Arms)[8] or the ArmaLite chamber, which are designed to handle both 5.56mm NATO and .223 Remington equally well. The dimensions and leade of the .223 Remington minimum C.I.P. chamber also differ from the 5.56mm NATO chamber specification.
Stole this from wiki - it is actually quite good and put everything to perspective:
While the 5.56mm NATO and .223 Remington cartridges and chamberings are very similar, they are not identical.
Military cases are generally made from thicker brass than commercial cases; this reduces the powder capacity (an important consideration for handloaders[6]), and 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.
The 5.56mm NATO chambering, known as a NATO or mil-spec chamber, has a longer leade, which is the distance between the mouth of the cartridge and the point at which the rifling engages the bullet. The .223 Remington chambering, known as SAAMI chamber, is allowed to have a shorter leade, and is only required to be proof tested to the lower SAAMI chamber pressure. To address these issues, various proprietary chambers exist, such as the Wylde chamber (Rock River Arms)[8] or the ArmaLite chamber, which are designed to handle both 5.56mm NATO and .223 Remington equally well. The dimensions and leade of the .223 Remington minimum C.I.P. chamber also differ from the 5.56mm NATO chamber specification.
Other than casing thickness and max pressures
1) The 5.56 round has a length .002 longer than the .223 round.
2) The 5.56 round has a slightly steeper shoulder angle.
Quote from an old American site, which IMHO, I agree with.
"What this all boils down to, is that unless your .223 is specifically chambered in 5.56 to accommodate the military ammunition, you run the risk damage to your rifle or yourself.
Colt and Bushmaster chamber ALL their .223 in 5.56. A few other companies chamber their AR15s in 5.56 as well. The big danger is in using 5.56 in bolt action rifles or the Ruger Mini 14, OR AR15s manufactured by some of the lesser known companies, particularly those that are not mil-spec or defense contractors."
This is exactly why certain firearms manuals SPECIFY NOT to use military ammunition in their rifles! They know! The combination of a slightly longer casing and steeper angle on the shoulder of the 5.56 round, can cause the bolt to not completely close and lock"
If munitions manufacturers are now using the two interchangeably, just putting them in different boxes...well, that I am unaware of and cannot substantiate either way..
1) The 5.56 round has a length .002 longer than the .223 round.
2) The 5.56 round has a slightly steeper shoulder angle.
Quote from an old American site, which IMHO, I agree with.
"What this all boils down to, is that unless your .223 is specifically chambered in 5.56 to accommodate the military ammunition, you run the risk damage to your rifle or yourself.
Colt and Bushmaster chamber ALL their .223 in 5.56. A few other companies chamber their AR15s in 5.56 as well. The big danger is in using 5.56 in bolt action rifles or the Ruger Mini 14, OR AR15s manufactured by some of the lesser known companies, particularly those that are not mil-spec or defense contractors."
This is exactly why certain firearms manuals SPECIFY NOT to use military ammunition in their rifles! They know! The combination of a slightly longer casing and steeper angle on the shoulder of the 5.56 round, can cause the bolt to not completely close and lock"
If munitions manufacturers are now using the two interchangeably, just putting them in different boxes...well, that I am unaware of and cannot substantiate either way..
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Here's some info on 223 and 5.6
223 5.6
Overall length 1.760 1.755
Head diam .377 .376
Rim diam . 378 .378
Neck lenght .191 .170
Rim thickness .045 .045
Shoulder diam .350 .340
Case capacity
grains water 28.12 30.13
Shoulder angle
degree 21.21 34.99
Hope this helps
JonnyBender
Second set of numbers on each line is for the 5.6
223 5.6
Overall length 1.760 1.755
Head diam .377 .376
Rim diam . 378 .378
Neck lenght .191 .170
Rim thickness .045 .045
Shoulder diam .350 .340
Case capacity
grains water 28.12 30.13
Shoulder angle
degree 21.21 34.99
Hope this helps
JonnyBender
Second set of numbers on each line is for the 5.6
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- Location
- Edmonton, AB
You mean 5.56, right?
SAMMI (US) and CIF (Europe) seem to operate differently - SAMMI put the maxi pressure at 52K psi, while CIF puts it up to 64psi.
I got a feeling that ( GUESS) that Europe .223 is the same as 556, but US 223 is 223. Someone can do some research to figure out exactly.
I got a feeling that ( GUESS) that Europe .223 is the same as 556, but US 223 is 223. Someone can do some research to figure out exactly.
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.
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.
http://en.wikipedia.org/wiki/5.56#5.56mm_NATO_versus_.223_Remington
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.
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.
http://en.wikipedia.org/wiki/5.56#5.56mm_NATO_versus_.223_Remington
According to The Handloaders Manual Of Cartridge Conversions when your looking for 5.6mm see .223 Remington and when looking for 5mm go to 223 Remington. On my first post I just removed the 2 on 5.62
Neck Dia. for 223 is .253 and the 5mm is .221
JonnyBender
Neck Dia. for 223 is .253 and the 5mm is .221
JonnyBender
Ar180shooter
CGN Ultra frequent flyer
- Location
- Ottawa, ON
Probably marked .223 for export reasons, but don't take my word for it. If you really want to know, a gunsmith could probably tell you.
