Stupid caliber question

[mdco2]

What is the difference between a .223 round and the 5.56 NATO rounds? If a gun is chambered in one can you use the other? And what is the difference in ballistics?

[DefensiveCarry.com]

[gasmitty]

Not stupid at all. The cartridges ARE different, and the differences are small but potentially "meaningful" - enough so to encourage one to know the differences.

Here's the best writeup I've found which explains the differences: 5.56 vs .223 – What You Know May Be Wrong - LuckyGunner.com Labs

[mdco2]

Thanks I'll read that in a little while.

[Crowman]

For the most part if you purchase an AR15 rated 5.56 you can not go wrong.

[QKShooter]

I agree with Crowman and you should just shop for a firearm chambered in 5.56. Problem solved.

[aus71383]

The simplest explanation (my understanding) is that the cartridges are the same dimensions - but the chambers are cut differently, and pressures/standards are different.

The .223 has less freebore, a sharper leade, etc... and is inherently more accurate because of it.
The 5.56 has more freebore, a more gradual leade, and is more forgiving (less accurate).

The link posted by gasmitty goes into much further detail, and is a good read if you like these sorts of things.

5.56 = shoot everything
.223 = don't shoot 5.56

[mdco2]

Alright thanks. I'm really looking into getting either an AR or Mini after I get my gun safe and was just wondering if there was a major difference in the two calibers. I think I've decieded to go with the .223 when the time comes because I would also like to get a good .223 bolt action to target shoot with. Now another thing is what are your feelings on the AR vs Mini? I know it has probly been asked before but since I'm already typing I will ask it again.

[sammage]

Also, be careful of cheaper brands a la DPMS, Bushmaster, etc who will state 5.56 mm on the barrel, when in fact are chambered in 223. Run a 5.56 round through there without reaming a chamber, and you will have problems.

[whoppo]

On the AR vs Mini topic:

Mini - Cool gun, but historically less accurate, fewer affordable aftermarket accessories...

AR - Can be extremely accurate, tons of inexpensive bolt-on toys as well as some very expensive ones, plentiful inexpensive magazines, easy to customize.

If you do decide to buy an AR, I would suggest shopping for one properly chambered in 5.56mm so you have the option of .223 ammo as well as often less expensive NATO ammo which is available in bulk.

best of luck and safe shooting!

[Smitty901]

The simplest explanation (my understanding) is that the cartridges are the same dimensions - but the chambers are cut differently, and pressures/standards are different.

The .223 has less freebore, a sharper leade, etc... and is inherently more accurate because of it.
The 5.56 has more freebore, a more gradual leade, and is more forgiving (less accurate).

The link posted by gasmitty goes into much further detail, and is a good read if you like these sorts of things.

5.56 = shoot everything
.223 = don't shoot 5.56

There it is simple and correct. Go with the 5.56 you have more options on rounds