What chamber ? 223 or 5.56

[J E Custom]

This is another one of those cases where you might get away with it but shouldn't.

There has always been a question about whether you could fire 223 rem and 5.56 ammo in the same chamber.

There are subtle differences in the two = Ammo for the 5.56 can be larger and in some cases cause pressure if fired in a 223 Rem chamber.

http://www.practicalmachinist.com/v...5-56-vs-223-223-vs-nato-vs-wylde-chambers.jpg

Instead of getting in to a big debate about should and should not I will leave it to the individual
which chamber to chose.

There is however a chamber that will accommodate both types of ammo without compromising
accuracy.

The 223 Wylde would be my choice if the intent is to fire both the 223 Rem and the 5.56 ammo in the rifle. I included the reamer specification for the Wylde in the link.

I know that some 223 rem chambers will accommodate both types of ammo, but if the 233 Rem chamber is very tight it can cause problems.

This is just more information to discuss, and maybe some good will come out of it.

J E CUSTOM

 

[CB11WYO]

Good call, thank you sir

 

[Trickymissfit]

the differences between the .223 and 5.56 are well known, and yet unknown by a few of us.

* case dimensions are identical

* barrel throats are a little different.

* chamber pressure specs are about ten percent higher with the 5.56 compared to the .223.

Now the chamber pressure spec has been blown out of proportion in my book. Some say your rifle will blow up in your face, and this always gives this old man a good laugh! A rifle that won't take 65K psi is a very weak design in my book! Even the AR platform was proofed out at far greater psi than this. The typical bolt action rifle that we often speak of here (Remington, Savage, Weatherby, Howa, Winchester 70) will easily handle 65K psi. Yet the 5.56 pressure spec is around 60K psi, while the .223 is spec'd at 55K psi. Please show me a Remington 700 that won't handle 70K psi!!! Blackhills loads the 5.56 NATO match ammo for the military. Their actual chamber pressure spec is 58K+ psi.

I've also heard the same crap about the 7.62x51 verses the commercial .308. One is spec's at a higher chamber pressure. How much escapes me, but it's probably around ten percent. The throat is a little different as well. Does this mean your Savage won't be able to shoot 7.62x51? NO!

Many years back Rifle Magazine published an article on shooting the .223/5.56 at 1000 yards. They went so far as to publish the chamber specs for both cartridges, and call out all the differences between the two. I lost the magazine when number two tossed me out of the house, and I wish I still had it. Think they later did the samething on the .308/7.62x51.
gary

 

[J E Custom]

Didn't mean to fire you up Gary, just wanted to let the newer shooters know the difference between the two rounds.

With ammo being harder to get we may not always have the choice and have to shoot what we can
get or have so why not chamber it so you can shoot both.

The main difference is that the 223 Rem Has a shorter throat and a shorter free bore and also less
lead angle . And with the higher load pressures and longer load lengths of the 5.56 I can be problematic. (My definition of problematic does not include blowing up a rifle/action), that would be called a disaster.

So with higher load pressures (I new they were loaded higher but did not know it was 10%higher) the 5.56 can be a really hard load in a 223 rem chamber. Like you, I have never heard of 5.56 ammo blowing up a 223 Rem, But have heard of blown primers and hard extraction So I though it would help some.

J E CUSTOM

 

[Trickymissfit]

Didn't mean to fire you up Gary, just wanted to let the newer shooters know the difference between the two rounds.

With ammo being harder to get we may not always have the choice and have to shoot what we can
get or have so why not chamber it so you can shoot both.

The main difference is that the 223 Rem Has a shorter throat and a shorter free bore and also less
lead angle . And with the higher load pressures and longer load lengths of the 5.56 I can be problematic. (My definition of problematic does not include blowing up a rifle/action), that would be called a disaster.

So with higher load pressures (I new they were loaded higher but did not know it was 10%higher) the 5.56 can be a really hard load in a 223 rem chamber. Like you, I have never heard of 5.56 ammo blowing up a 223 Rem, But have heard of blown primers and hard extraction So I though it would help some.

J E CUSTOM

years back I got into an online shouting match with three guys that swore the 5.56 will blow up a good rifle! I commented that I'd shot several hundred 5.56 rounds thru a .223 bolt gun without an issue one. (Lake City match). Then it evolved into the AR platform, and I got another good laugh. Where's the chamber pressure, I asked? Modern AR's have a very stiff buffer spring and a heavy buffer. Yes we'll see an increase in recoil, but not much. I've never seen a primer pushed out, but could see this.

The real issue with the AR is the chamber itself and not the throat. A mil spec chamber is not perfectly round.
gary

 

[FEENIX]

Ditto on the .223Wylde, that's what wife's AR is.

 

[shortgrass]

I've got a Rem. Model 7 action with the .378 bolt face. When I barrel it, it'll be chambered for the .223 Wylde. It'll be as accurate as it needs to be for a "walking varminter'. Probably use a 1 in 9 or 1-8 twist. Won't need anything 'tighter' as I'll not be shooting any tracer ammo. My match AR is chambered in .223 Wylde. Shoots better than my old eyes can. It's all about ammo 'flexibility' with acceptable accuracy.

 

[Edd]

http://www.longrangehunting.com/forums/f37/differences-223s-142195/

http://ar15barrels.com/data/223-556.pdf

 

[J E Custom]

http://www.longrangehunting.com/forums/f37/differences-223s-142195/

http://ar15barrels.com/data/223-556.pdf

Thanks Edd.

Nice to see all of the different dimensions side by side for comparison

That may be easier for those that are not used to looking at reamer drawings

It also shoes the many variations of this cartridge.

PS: I am not pushing the 223 Wylde, just trying to give others an option of chambers and ammo

Thanks Again.

J E CUSTOM

 

[geo4061]

Jerry what about accuracy? Is the Wylde, 223, or 5.56 the most accurate? So, I could shoot 5.56 in my 223 in a pinch, however, is there any damage done to chamber or barrel?

 

[J E Custom]

Jerry what about accuracy? Is the Wylde, 223, or 5.56 the most accurate? So, I could shoot 5.56 in my 223 in a pinch, however, is there any damage done to chamber or barrel?

There should be no difference in accuracy. If the head space is set close. (.0000 to .0005) the bolt
and the case shoulder will center the round. Al three cases head space the same.

Should you shoot 5.56 ammo in your 223 REM chamber ? I don't recommend it (The reason for this post) even though you may get away with it. I don't think you would damage the rifle or the chamber, but you could hurt the brass with high pressures of the 5.56 in the 223 Rem chambers
due to all the things discussed in earlier post.

J E CUSTOM

 

[shortgrass]

Use the caliber marked on your barrel for best accuracy. When I barrel my Model 7, and cut a .223 Wylde chamber, I'll be shooting handloads (probably 69g. SMK). But if I get in a pinch, I can use factory loaded .223 Rem. or 5.56mm and expect reasonable accurcy from either. Probably not as good as good handloads worked up for that rifle, but reasonable. The .223 Wylde chamber is a compromise, a compromise that should be easily over come with a bit of "handload development".