AR Build Question

[porscheboy]

Hey guys, I just started my first AR build a couple weeks ago, and have the lower assembled now, now I'm turning my attention to the upper assembly. I already have a good idea of what I want in the upper, and when looking at barrels on Midway, about 75% of them are chambered in 5.56. I plan on utilizing the .223 round in my build. What are the dissadvantages to shooting .223 in a 5.56 chamber? Or is there no difference at all?
-Thanks in advance..

 

[redbullitt]

223 runs just fine in my 5.56 chamber. You will hear all kinds of opinions on it, and may people do different things. It is just going to be up to you.

If I were to order a 5.56, I personally would use 223 with no worries.

 

[Deus Machina]

5.56 chambers are slightly loosen and, IIRC, have a slightly different throat.

.223 fires perfectly fine in a 5.56, but 5.56 in a .223 may or may not be advisable, depending on the specs.

 

[Grunt Medic TXARNG]

You will see some barrels with what is described as a 'wylde' chamber which has been specifically designed to shoot both .223 and 5.56 loadings. And as has been mentioned, firing .223 in a 5.56 chambered rifle poses no problems - but do not fire5.56 ammo in a gun chambered for .223, as this can possibly result in an overpressure situation.

 

[Deus Machina]

On that, I would feel just fine shooting 5.56 out of a .223 barrel, if I dropped it at a gunsmith to have them check that it was in spec and would handle the pressure. Frankly, if it's a true .223, it should be a little too tight for 5.56 anyway.

If you're building a target rifle, feel free to opt for the tighter-specced .223 barrels and use only .223. 5.56 barrels would be, IMO, better all around for a 'fighting' rifle, but may be a hair less accurate from the bench.

 

[Ridgerunner23]

I build AR-15 and other types of assault rifles. This is a common question I get asked…”Should I get 223 or 5.56?”. I tell my costumers that I prefer 5.56 due to the fact you can shoot either 223 of 5.56. There again it’s totally up to them after all its their money. Check out Del-ton Inc. they have excellent AR-15 parts at a reasonable price, I buy from them quite a bit.
http://www.del-ton.com/

 

[SoulLessGinger]

The only difference between a .223 and a 5.56 chamber is the throat being a bit longer on the 5.56.

Otherewise it is demensionally identical. For accuracy you want a .223 chamber. For versatility and the ability to shoot hotter ammo, 5.56 is best.

 

[Tirod]

How much accuracy difference is there for the small change in leade?

I think we might be confusing the typical non chrome .223 with the 5.56, which is often chromed, and typically milspec 2MOA. Chroming doesn't add anything to accuracy because it often can't hold a very low tolerance. Non chrome isn't rifled oversized and plated back, the operation gives you exactly what you get.

.223 is likely more accurate simply because the barrels are, not because of the leade.