5.56/.223 verification

[awgrizzly]

I know you guys have answered this over and over, but please forgive that I'm just a bit dense.

I have a bunch of new 5.56x45 brass I want to reload.

The 5.56 is said to have a longer throat than the .223 unless the gun is chambered to accept both. I assume that does not mean that the 5.56 neck and overall case length are longer, just that longer bullets may be used. Other than the brass being thicker and the capacity slightly less, is there anything special I need to do in loading them according to .223 AR15 specs and shooting them in a gun chambered for the .223?

From my searches here that is what I understand... I just need confirmation.

Thank you

 

[cfullgraf]

5.56 brass and 223 Remington brass are the same dimensions.

5.56 Nato chambers are differennt from 223 Remington chambers.

It is a myth that all 5.56 Nato brass is heavier than all 223 Reminton brass. Several years ago I measured 500-600 each of Winchester 223 Remington and Lake City 5.56 Nato brass. lake City was about 10 grains lighter on average than the Winchester.

 

[rcmodel]

I agree all GI brass is not heavier / with less capacity then all commercial brass.
I have old LC 5.56 GI brass that is lighter then recent Rem commercial .223 brass.

More here about 5.56/.223 case weights 1/4 way down the page.
http://www.6mmbr.com/223rem.html

Bottom line is, the only way to know if they are different is to size, trim and weigh them, then compare them to your commercial brass that has been sized & trimmed to the same length.

Whichever one weighs more has less capacity.

The other thing is, it really doesn't matter unless you load balls-to-the-wall max loads.
I don't, as the .223 will do anything it is capable of doing at 50,000 PSI as opposed to 59,306 PSI with blown primers.

rc