Shooting .223 in a 5.56 rifle
- Thread starter Angleiron
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Maverick223
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I don't believe that the thickness at the neck is any different from the .223, and the bullet diameter is definitely the same (.224).
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chuckusaret
member
Hey guys, SAAMI has been saying since the late 1970's not to use 5.56 in weapons marked .223 only and I take their word and don't do it.
SAAMI info: http://www.thegunzone.com/556v223.html
SAAMI info: http://www.thegunzone.com/556v223.html
I shoot both with zero problems. Accuracy is not noticeably different, but then again, I'm not competing for match accuracy anyway. I'm told that my 5.56 ammo is louder than my .223 ammo. From behind the barrel, with ear protection, I can't tell.
Bottom line is to get a 5.56 chamber. Then you're completely fine.
Bottom line is to get a 5.56 chamber. Then you're completely fine.
Maverick223
Member
Edited post 28 to read: "...don't believe that the thickness at the neck is any different...", mistakenly said that the neck was of a different thickness.
greyling22
Member
I was just asking because I still had a few 556's loaded as 223's and didn't know if it was safe to shoot them in my new 223 bolt gun. sounds like I am good to go.
Maverick223
Member
With a .223 chamber (such as yours) I am not positive, but I believe you will be fine. With a 5.56 chamber (such as the O.P.) I know you're safe with 5.56 and .223, as well as 5.56 resized using .223 dies.
I don't know what you consider "slightly" but in the case of 5.56 NATO vs. .223 from AR w/ 20" 5.56 chambered barrel the 62gr .223 loads clock in at ~3000fps while M855 clocks in at ~3200fps. I haven't chronoed it yet but M193 should clock in at 3300+ fps from a 20" barrel while 55gr .223 normally clocks in at 3200 fps from a 24" barrel. That's a very big slightly.
7.62 NATO and .308 are the opposite so far as max pressures are concerned but I don't think there's much difference here commerically unless you get into the hot and heavy or handloaded .308 loads. If you where to beleive the reloading manuals though a 150gr bullet can be pushed to 2900fps when hitting max .308 pressures while typical 7.62 NATO loads clock in at what 2700fps?
You also have to look at, in the case of .223/5.56, what's using what chamber? Semi-autos typically use 5.56 chambers (or a version of) while bolt guns typically use .223 chambers. It's pretty well known that gas guns usually show pressure signs sooner than bolt guns and that bolt guns are usually stronger action wise. I doubt other than a hard to extract case every once in a while it would matter much to fire 5.56 in a .223 chambered modern bolt gun.
With 7.62 and .308, I wouldn't run some hot and heavy .308 loads through a mil surp 7.62 gun. I think this is a more dangerous situtation because the rolls are reverse and the semi-auto is getting the higher pressure ammo. Add that to the fact that mil surps are usually older guns not designed for anything near what we can load today. Now their newer decendants such as new DSA FAL, PTR-91, M1A, AR-10, etc. I doubt there's much issue.
SpeedAKL
Member
High quality factory .223 will out-shoot 5.56 milsurp with boring regularity so whatever minute accuracy differences there may be in shooting SAAMI .223 out of a 5.56 chamber will be more than made up for.
The only military issued ammo that will approach civilian .223 match loads is the Mk.262 ammo that SOCOM has been known to use. This is loaded with the 77-gr sierra match king bullet. A very similar load is available through Black Hills.
The only military issued ammo that will approach civilian .223 match loads is the Mk.262 ammo that SOCOM has been known to use. This is loaded with the 77-gr sierra match king bullet. A very similar load is available through Black Hills.
dogngun
Member
Chambers are usually a little larger in military rifles to allow for slight variations in ammo, dirt, etc, and the brass is slightly thicker, and primers slightly harder.
I doubt there is much other difference.
mark
I doubt there is much other difference.
mark
Kurt D
I looked up the chamber pressures and they were like 2,000-3,000 PSI greater on the 5.56. That's not really a whole lot (maybe 4% or so) and is probably mostly due to the thicker case on the military rounds. I would not be surprised if the ammo manufacturers used the same powder charge for commercial 223 and military 5.56 but the cases for each are different in thickness causing the slightly elevated pressure in the military rounds. Most reloading manuals warn to reduce reloads slightly with military cases due to the added thickness raising pressures a tad.
Of course gun makers and ammo makers issue the usual dire warnings on advice of their lawyers. But like I said, I have used commercial and military ammo interchangeably in my 223 and 308 rifles, both auto and bolt, without any issues. I have never HEARD of anyone having any sort of problem.
An early 223 rifle made before the advent of the longer 68 grain bullet might be a concern due to lack of free-bore with such ammo, but I think recently made rifles have enough chamber length to use them. You always want to be aware of overall cartridge length in any rifle.
I looked up the chamber pressures and they were like 2,000-3,000 PSI greater on the 5.56. That's not really a whole lot (maybe 4% or so) and is probably mostly due to the thicker case on the military rounds. I would not be surprised if the ammo manufacturers used the same powder charge for commercial 223 and military 5.56 but the cases for each are different in thickness causing the slightly elevated pressure in the military rounds. Most reloading manuals warn to reduce reloads slightly with military cases due to the added thickness raising pressures a tad.
Of course gun makers and ammo makers issue the usual dire warnings on advice of their lawyers. But like I said, I have used commercial and military ammo interchangeably in my 223 and 308 rifles, both auto and bolt, without any issues. I have never HEARD of anyone having any sort of problem.
An early 223 rifle made before the advent of the longer 68 grain bullet might be a concern due to lack of free-bore with such ammo, but I think recently made rifles have enough chamber length to use them. You always want to be aware of overall cartridge length in any rifle.
Offfhand
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REMODEL, thanks for getting back with response to my question. It's easy to understand why the Sako would have a pressure problem, not just with 5.56 Mil ammo but with standard .223 as well. The same with the 40-X if it has a BR dedicated chamber and neck specs. The Remington custom shop BR neck is .246" unless specified otherwise by customer. This requires turning the case necks to .010" for ample, yet close fit. Standard neck diameter of 5.56 and commercial .223 ammo averages close to .248." Which makes it difficult to force into a BR chamber, requiring a hard, determined push on the bolt to get it closed, if at all. A squeeze that tight would certainly result in blown primers, etc. with any otherwise standard 5.56 or .223 load. But in both examples the situations described would seem to be more related to non-standard chamber or barrel specs. Where I work we have a number of "slave" .223 Cal rifles used for evaluating 5.56 Mil and .223 commercial loadings. These have standard SAAMI chambers and I'm not aware of there having been any problems. Which is why I'm trying to get reports from outside observers such as yourself. Thanks again
Wait, the SAAMI unsafe combinations linked to (http://www.saami.org/Unsafe_Combinations.cfm) says that a 9mm Luger (Parabellum) chamber is unsafe with 9mm NATO (Military)
I thought that 9x19mm Luger, aka Parabellum, was 9mm NATO. I'll have to Google this now. At any rate, the only 9mm I own is a Beretta 92FS and I'm pretty sure it's 9mm NATO.
I thought that 9x19mm Luger, aka Parabellum, was 9mm NATO. I'll have to Google this now. At any rate, the only 9mm I own is a Beretta 92FS and I'm pretty sure it's 9mm NATO.
rcmodel
Member in memoriam
Same difference.
9mm NATO is loaded to higher pressure then American SAAMI standard pressure 9mm Luger.
It's more like +P SAAMI spec ammo I suppose.
Whatever it is, your Beretta 92, and most all other 9mm pistols with a military design background were made to shoot it.
As for .223/5.56 pressure comparisons?
Can't do it, because the military testing measures pressure in a different place in the barrel then SAAMI specs call for.
Whatever GI pressure specs you find is Apples & Oranges when compared to commercial ammo pressure.
rc
9mm NATO is loaded to higher pressure then American SAAMI standard pressure 9mm Luger.
It's more like +P SAAMI spec ammo I suppose.
Whatever it is, your Beretta 92, and most all other 9mm pistols with a military design background were made to shoot it.
As for .223/5.56 pressure comparisons?
Can't do it, because the military testing measures pressure in a different place in the barrel then SAAMI specs call for.
Whatever GI pressure specs you find is Apples & Oranges when compared to commercial ammo pressure.
rc
The only 5.56x45mm rifle I own is a Sig 556 and it says 5.56 NATO right on the side of the thing
Come to think of it, didn't the Seals crack the slides on some of the early test M9s by firing +P 9mm ammo?
Quick lookup on Wikipedia
Come to think of it, didn't the Seals crack the slides on some of the early test M9s by firing +P 9mm ammo?
Quick lookup on Wikipedia
rcmodel
Member in memoriam
The ammo that was cracking slides was over-pressure & out of NATO spec to start with.
Following the slide cracking incidents, a change was made to a different power among other things.
rc
Following the slide cracking incidents, a change was made to a different power among other things.
rc
kenkel98
Member
Ok guys,
I don't mean to beat a dead horse about this but...
I have a Ruger Mini-14 Ranch built in 1999. It is labeled .223 on the receiver. I haven't taken it apart to see if the barrel is stamped 5.56, but according to the manual, it will shoot both the .223 and the 5.56.
I have a Colt AR-15 SP1 built around 1973 and it is stamped .223 on the lower. Nothing stamped on the barrel, not even the twist rate.
I have been shooting both .223 and 5.56 ammo in the Ruger for the last 15 years or so. Of course, I really don't shoot it that often. It has probably had less than 1000 rounds put through it but still, no problems with the 5.56 ammo. That's not to say it won't happen, but...
The AR has had quite a few more than that run through it. Both 5.56 and .223. I have always used 55 gr. ammo assuming the twist rate is probably 12.1. Again, never had a problem. Again, not to say it won't happen, but...
I have not seen any difference in accuracy, keeping in mind I have not locked these guns into vices and shot them at 500 yards. I normally shoot between 75 and 150 yards.
I have been a gun "nut" for over 35 years and consider myself very knowledgable. But, I have learned a lot here tonight. I worked part time in a gun store for years, mostly just for the fun of it, but I never knew about the differences between the .223 and the 5.56 rounds. I had always been told that the 5.56 was the military or NATO designation for the .223 and that they were the same round. And I was in the Air Force!! Of course, I only had to shoot the M-16 twice during my 4 years.
I plan to reload the .223/5.56 and have all the dies, powder and bullets to do so.
Everytime I login to this web site I learn something new.
Just my 2 cents worth..
Thanks again THR for being here for us.
K
I don't mean to beat a dead horse about this but...
I have a Ruger Mini-14 Ranch built in 1999. It is labeled .223 on the receiver. I haven't taken it apart to see if the barrel is stamped 5.56, but according to the manual, it will shoot both the .223 and the 5.56.
I have a Colt AR-15 SP1 built around 1973 and it is stamped .223 on the lower. Nothing stamped on the barrel, not even the twist rate.
I have been shooting both .223 and 5.56 ammo in the Ruger for the last 15 years or so. Of course, I really don't shoot it that often. It has probably had less than 1000 rounds put through it but still, no problems with the 5.56 ammo. That's not to say it won't happen, but...
The AR has had quite a few more than that run through it. Both 5.56 and .223. I have always used 55 gr. ammo assuming the twist rate is probably 12.1. Again, never had a problem. Again, not to say it won't happen, but...
I have not seen any difference in accuracy, keeping in mind I have not locked these guns into vices and shot them at 500 yards. I normally shoot between 75 and 150 yards.
I have been a gun "nut" for over 35 years and consider myself very knowledgable. But, I have learned a lot here tonight. I worked part time in a gun store for years, mostly just for the fun of it, but I never knew about the differences between the .223 and the 5.56 rounds. I had always been told that the 5.56 was the military or NATO designation for the .223 and that they were the same round. And I was in the Air Force!! Of course, I only had to shoot the M-16 twice during my 4 years.
I plan to reload the .223/5.56 and have all the dies, powder and bullets to do so.
Everytime I login to this web site I learn something new.
Just my 2 cents worth..
Thanks again THR for being here for us.
K
ugaarguy
Member
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- Mar 19, 2006
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- 13,828
There's the answer on your Mini-14.
It's probably a 5.56 chambered bbl, being an older Colt, but that's a bit before my time. I owned an SP-1 of 1986 vintage (IIRC that's when the Marine who sold it to me told me he bought it new) which was stamped .223 on the lower, but had the standard C MP 5.56 1:12 stamped on the bbl forward of the FSB. Have you taken off the handguards to see if the barrel is stamped underneath them?
This is the most overblown "controversy" in the gun world and amounts to little more than two old ladies arguing over whether a dress is black or Navy blue.
It doesn't matter. .223 Remington and 5.56x45 are interchangeable designations for the same round and one can't measure the difference between cartidges loaded to the respective specifications doesn't exist.
Using highly sensitive and precise tools one could likely measure the minute variations in chambers, but you can't measure the difference in the cartridges themselves.
It doesn't matter. .223 Remington and 5.56x45 are interchangeable designations for the same round and one can't measure the difference between cartidges loaded to the respective specifications doesn't exist.
Using highly sensitive and precise tools one could likely measure the minute variations in chambers, but you can't measure the difference in the cartridges themselves.
Colt SP1s were 556 Nato chambered. Owned three, with the first one back in the mid-70's. All shot LC mil surp 5.56.
I guess gun makers are still stamping whatever they want on barrels and receivers, further adding to the confusion.
As posted earlier, even Saigas have ".223 Rem" stamped on their receivers and magazines. The manual lists the cartridge as ".223 Rem (5.56x45)".
M
I guess gun makers are still stamping whatever they want on barrels and receivers, further adding to the confusion.
As posted earlier, even Saigas have ".223 Rem" stamped on their receivers and magazines. The manual lists the cartridge as ".223 Rem (5.56x45)".
M
DJnRF
Member
This post may be archived, but this is relative, and explanatory.
" The two major changes between .223 Rem and 5.56 NATO are that the throat length is longer and the chamber pressure is measured differently.
“Throat length” is defined as the distance between the end of the cartridge neck and the point at which the rifling in the barrel engages the bullet. In the above image the throat length is clearly identified as the green markings on the bullet and marked as (a) on the barrel.
A longer throat length will allow you to load a heavier bullet (since length is the only way to increase weight with a fixed diameter projectile and using the same materials), which are more accurate at long distances and such. But with lighter bullets, a longer throat means that the bullet will not engage the rifling as quickly as desired and may lead to concentricity errors as the bullet wobbles off center before hitting the rifling. That’s a bad thing, and negatively impacts accuracy.
A shorter throat length means lighter bullets are more accurate. But if you try to load a longer bullet, the short throat length will push the bullet further into the case which increases chamber pressure and can lead to explosions and other bad things.
So, in short, longer is better. And 5.56 NATO is longer."
This is an excerpt on this issue from:
http://www.thetruthaboutguns.com/20...rn-whats-the-difference-between-5-56-and-223/
The whole point being that if you have a 5.56 chambered barrel, you
are safe to use the .223, But, ..... NOT the other way around!
Dave.
" The two major changes between .223 Rem and 5.56 NATO are that the throat length is longer and the chamber pressure is measured differently.
“Throat length” is defined as the distance between the end of the cartridge neck and the point at which the rifling in the barrel engages the bullet. In the above image the throat length is clearly identified as the green markings on the bullet and marked as (a) on the barrel.
A longer throat length will allow you to load a heavier bullet (since length is the only way to increase weight with a fixed diameter projectile and using the same materials), which are more accurate at long distances and such. But with lighter bullets, a longer throat means that the bullet will not engage the rifling as quickly as desired and may lead to concentricity errors as the bullet wobbles off center before hitting the rifling. That’s a bad thing, and negatively impacts accuracy.
A shorter throat length means lighter bullets are more accurate. But if you try to load a longer bullet, the short throat length will push the bullet further into the case which increases chamber pressure and can lead to explosions and other bad things.
So, in short, longer is better. And 5.56 NATO is longer."
This is an excerpt on this issue from:
http://www.thetruthaboutguns.com/20...rn-whats-the-difference-between-5-56-and-223/
The whole point being that if you have a 5.56 chambered barrel, you
are safe to use the .223, But, ..... NOT the other way around!
Dave.
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