.223 or 5.56??
I'm sure this has been addressed ad nauseum here, but I am asking again about ammo differences....I have an unfired piston driven Bushmaster AR XM15 E2S....I can't find the manual for it....is it a .223 barrel or a 5.56? I am confused. Can I shoot either from it? Is there a difference between break-in ammo and regular shooting ammo? Pardon my ignorance and thanks for any advice.
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The chamber type is usually stamped on the barrel like the twist rate. Sometimes it is difficult to see. Look with light coming across the surface at an angle to find it. 0 -
You can safely shoot either in it. Don't pay any attention to the gun shop commandos who are going to tell you that it will self destruct if you shoot commercial .223 in a 5.56 barrel, or vise versa. There nothing but bunch of Chicken Little's who don't have a social life and spend way to much time gossiping on the net. 0 -
quote:Originally posted by rufe-snow
You can safely shoot either in it. Don't pay any attention to the gun shop commandos who are going to tell you that it will self destruct if you shoot commercial .223 in a 5.56 barrel, or vise versa. There nothing but bunch of Chicken Little's who don't have a social life and spend way to much time gossiping on the net.
^^^ The above b.s. is incorrect information and the poster is talking out of his rectum...
You can safely shoot .223 in a rifle chambered for 5.56mm. Do not shoot 5.56mm in a .223 chambered firearm.
While the external case dimensions are very similar, the .223 Remington and 5.56x45mm differ in both maximum pressure and chamber shape. The maximum and mean pressures for some varieties of the 5.56 mm (different cartridge designations have different standards) exceed the SAAMI maximums for the .223 Remington, and the methods for measuring pressures differ between NATO and SAAMI. The 5.56 mm chamber specification has also changed over time since its adoption, as the current military loading (NATO SS-109 or US M855) uses longer, heavier bullets than the original loading did. This has resulted in a lengthening of the throat in the 5.56 mm chamber. Thus, while .223 Remington ammunition can be safely fired in a 5.56 mm chambered gun, firing 5.56 mm ammunition in a .223 Remington chamber may produce pressures in excess of even the 5.56 mm specifications due to the shorter throat.0 -
quote:Originally posted by 17tobyracing
quote:Originally posted by rufe-snow
You can safely shoot either in it. Don't pay any attention to the gun shop commandos who are going to tell you that it will self destruct if you shoot commercial .223 in a 5.56 barrel, or vise versa. There nothing but bunch of Chicken Little's who don't have a social life and spend way to much time gossiping on the net.
^^^ The above b.s. is incorrect information and the poster is talking out of his rectum...
You can safely shoot .223 in a rifle chambered for 5.56mm. Do not shoot 5.56mm in a .223 chambered firearm.
While the external case dimensions are very similar, the .223 Remington and 5.56x45mm differ in both maximum pressure and chamber shape. The maximum and mean pressures for some varieties of the 5.56 mm (different cartridge designations have different standards) exceed the SAAMI maximums for the .223 Remington, and the methods for measuring pressures differ between NATO and SAAMI. The 5.56 mm chamber specification has also changed over time since its adoption, as the current military loading (NATO SS-109 or US M855) uses longer, heavier bullets than the original loading did. This has resulted in a lengthening of the throat in the 5.56 mm chamber. Thus, while .223 Remington ammunition can be safely fired in a 5.56 mm chambered gun, firing 5.56 mm ammunition in a .223 Remington chamber may produce pressures in excess of even the 5.56 mm specifications due to the shorter throat.
Horse Pucky! I bought my first Colt sporter back in the 60's. Since then I've owned first generation Bushmasters, AR 180's, Colt M 16's assembled on commercial lowers, etc.etc. Shot every thing and anything I could get my hands on in them, military, commercial, reloads etc. Only time I ever had any problems was years ago with the 180. I bought a bunch of Norma FMJ that would blow the primers. It almost seemed that somebody had mistakenly loaded it with small pistol primers rather then small rifle primers.
I first noticed these Chicken Little's pushing their fantasies regarding the so called danger of shooting .223 in 5.56 chambers and vice versa on the net 10/12 years ago. I've called BS on it in the past and I will do it in the future. Ain't nothing going to happen to either you or your rifle from shooting either .223 or 5.56 in it, no mater how it's chambered.0 -
Well clearly stamped on the gun is .223 Cal 5.56....lol....so I guess Bushmaster says I can fire either....very confusing. 0 -
Forgemonkey I went to thegunzonme and read the article...I see your reason for caution....but why would Bushmaster stamp right on the gun both .223 AND 5.56 if one round is more appropriate than the other? I guess I am going to call them and ask.... 0 -
quote:Originally posted by eastwood396
Well clearly stamped on the gun is .223 Cal 5.56....lol....so I guess Bushmaster says I can fire either....very confusing.
Bushmaster might have put a WYLDE chamber in it if it's marked that way. The WYLDE chamber is made to shoot either round.
A 223 chamber is not supposed to be fired with 5.56 NATO ammo.0 -
eastwood396,
There are several 'adjusted' chambers used in AR15 platforms, most of which will accommodate both cartridges since that's what they were designed to do.
If you do a search you'll find the list of chambers with the dimensional changes which I have posted several times in the past.
Best.0
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