Does Lake City make both 5.56 & 223 ammo or only 5.56? The only marking on the Lake City once fired brass I have isn't marked either way. Just LC on the case head.

My LC brass is the same way.

How many 223 Remington rifles are in the military? Lake City is a .gov entity run by a contractor that gets to sell excess military production on the civilian market. Adding it up should answer your question.

5.56 only marked LC.

Even have some Winchester packed 5.56 55 grain fmj with LC headstamp.

Well duh, Up until Winchester took over I’ve got Federal 556 55 and 62 green tip that’s all LC brass from when they ran LC. Amazing isn’t it.

Good thing you've got everything figured out.

Lake City does make 223 REM stamped ammo. I just reloaded 150 pieces of them. I think they came in factory boxes of the brand Herters. I would post a picture, but it’s a pain for me as I’m ignorant about adjusting the size. Just for this website, others don’t make a big deal about the size or they have some tool that adjusts it automatically to their liking and I post all the time.

Postimages.org is your friend.

I was able to find it online and maybe it’s the right size and will show.

Since Winchester took over the LC plant I have seen both LC 5.56 and LC .223 headstamps.
Federal used to do the same when they ran the Lake City plant but used the FC headstamp on their .223 loads.

I could have phrased the original question a lot better. Does all once fired 223 shaped brass with a LC on the case head come from 5.56 ammo with a military crimp primer?

I believe everything that comes off the LC lines is crimped with the exception of their unprimed brass which is occasionally available.
Removing the crimp is no big deal when you consider your getting very good brass.

Thanks to all for the info,