how to tell 223/556 commercial brass from military brass?

[safaridave]

I am close to jumping in with reloading to be able to shoot more. I have been saving my brass (mostly military 556) and picking up range brass when I see the opportunity.

So my question is this-

I have bags of mixed brass, mostly federal/winchester mil brass, but also some others that may or may not be mil brass. How can I tell?

Also, I hear that reloading mil brass is different than commercial. Notably the case volume in mil brass is smaller? How much smaller? how will this affect the amount of powder, if at all? I have heard that 1 grain of powder less is the rule of thumb?

Thanks from a noob.

[21SF]

Usually the military brass has a Nato stamp that looks like a circle with a cross inside.

[freonr22]

Military brass has a primer crimp normally, that will have to be removed to reload...

[CSACANNONEER]

Headstamps are the best way to ID any brass. Also, military brass will have primers crimped or staked in while, most commercial brass won't.

[Justintoxicated]

Wow one grain of powder less?

[damndave]

Mil brass usually has a crimped primer. If you do a google search you can see pictures of known headstamps. One forsure is a + with a circle around it.

Mil brass is thicker walled so the inside capacity is less thus producing more pressure.

I would separate my brass by headstamp and load that way.