themadbomber
New member
It is not recommended to fire 5.56 in a .223, but are the bolt assemblies interchangable? Also, does the whole chamber need to be 5.56, the barrel, or both?
Questions about my AR 15
- Thread starter themadbomber
- Start date
The chamber is part of the barrel. It is the part where the round/cartridge "sits" prior to and when being fired. As long as it is 5.56 you can shoot both safely. If you want to get really crazy, you can get a .223 Wylde chambered barrel, which is a happy medium between the two and can shoot both safely while being theoretically the best compromise in accuracy for shooting both.
Bolt assemblies are the same thing, there aren't separate 5.56/.223 bolt assemblies.
Bolt assemblies are the same thing, there aren't separate 5.56/.223 bolt assemblies.
themadbomber
New member
Thank you, so that means I can just keep my upper and just switch out to a 5.56 barrel, correct?
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Palmetto-Pride
New member
Yes.........but some will probably tell you to have the head space checked by a gunsmith to be absolutely sure its with in tolerance........uh oh I just opened up another can of worms......lol
marine6680
New member
Are you sure your barrel isn't 5.56?
If it is an AR, and not a special purpose one built for hunting or target, they are usually 5.56 and not 223.
The barrel will have the caliber stamped on it... the caliber marking on the receiver isn't really useful, as it could be wrong.
If it is an AR, and not a special purpose one built for hunting or target, they are usually 5.56 and not 223.
The barrel will have the caliber stamped on it... the caliber marking on the receiver isn't really useful, as it could be wrong.
Here is my take on things. When I was in the military, Uncle Sam provided me with an M-16 to use in training and combat in Nam along with the ammunition. I never thought about it.
A month ago I bought my first semi-automatic firearm in .223 Remington caliber. It states on the barrel 5.56, and my understanding is it will shoot both 5.56 & .223 Remington. I bought a small amount of .223 Remington ammunition until I could acquire the dies, bullets and brass for reloading. The reloading manuals provided the recipes I needed for reloading. I follow those religiously. The reloading manuals state for .223 Remington. Some of the head stamps of once fired brass show .223 Remington and some state 5.56.
No problem, they are all to spec. after I finish reloading each round.
I am good to go~
A month ago I bought my first semi-automatic firearm in .223 Remington caliber. It states on the barrel 5.56, and my understanding is it will shoot both 5.56 & .223 Remington. I bought a small amount of .223 Remington ammunition until I could acquire the dies, bullets and brass for reloading. The reloading manuals provided the recipes I needed for reloading. I follow those religiously. The reloading manuals state for .223 Remington. Some of the head stamps of once fired brass show .223 Remington and some state 5.56.
No problem, they are all to spec. after I finish reloading each round.
I am good to go~
The interchangeability of .223 and 5.56 is a common topic of discussion.
Some do it all the time, others, not so much.
There seem to be other malfunctions that happen at a much higher rate than documented cases of the wrong cartridge blowing one up. Partially extracted cases blowing out seem to be one common case, and bolt bounce from carbine gassed rifles is often mentioned as a cause.
As said, check the barrel for it's actual chambering, what is rollmarked on a lower in terms of caliber means nothing. Mine says "mulitcal" and I am quite sure it won't take anything but 6.8SPC.
Some do it all the time, others, not so much.
There seem to be other malfunctions that happen at a much higher rate than documented cases of the wrong cartridge blowing one up. Partially extracted cases blowing out seem to be one common case, and bolt bounce from carbine gassed rifles is often mentioned as a cause.
As said, check the barrel for it's actual chambering, what is rollmarked on a lower in terms of caliber means nothing. Mine says "mulitcal" and I am quite sure it won't take anything but 6.8SPC.
"A month ago I bought my first semi-automatic firearm in .223 Remington caliber. It states on the barrel 5.56, and my understanding is it will shoot both 5.56 & .223 Remington."
If it says "5.56" on the barrel, it's NOT a .223.
No 5.56 in .223 is a blanket statement for the CMA rifle manufacturers. Yes, you MAY encounter higher pressures when firing SOME types of 5.56 ammo in SOME .223 chambers.
Most specifically, firing 855 ammo in a short throated chamber (or one with a very abrupt transition from chamber to rifling)is very likely to cause this. 855 is loaded fairly hot(to achieve max velocity in shorter barrels) and has a long bullet with a fairly stiff jacket which is entering the rifling while the powder is still making lots of whoopie.
I wouldn't shoot 855 in a .223 chamber but I have fired several ammo cans of M193 (55FMJ--REAL military ammo-not aftermarket commercial wannabe stuff) w/o any issues except in one H&R single shot. The H&R has a short throat AND a very abrupt transition from neck to rifling so I'm pretty sure something very unsatisfactory would result from any attempt to fire 855 ammo in that particular rifle.
If it says "5.56" on the barrel, it's NOT a .223.
No 5.56 in .223 is a blanket statement for the CMA rifle manufacturers. Yes, you MAY encounter higher pressures when firing SOME types of 5.56 ammo in SOME .223 chambers.
Most specifically, firing 855 ammo in a short throated chamber (or one with a very abrupt transition from chamber to rifling)is very likely to cause this. 855 is loaded fairly hot(to achieve max velocity in shorter barrels) and has a long bullet with a fairly stiff jacket which is entering the rifling while the powder is still making lots of whoopie.
I wouldn't shoot 855 in a .223 chamber but I have fired several ammo cans of M193 (55FMJ--REAL military ammo-not aftermarket commercial wannabe stuff) w/o any issues except in one H&R single shot. The H&R has a short throat AND a very abrupt transition from neck to rifling so I'm pretty sure something very unsatisfactory would result from any attempt to fire 855 ammo in that particular rifle.