I sorted thru a half bucket of .223 brass I picked up at the local range. The most abundant by far was a bunch of Lake City with various dated headstamps.
So I ended up with about 100 LC 20 (Lake City 2020) that looked decent enough to use.
I looked at several reloading manuals and found .223 max case OAL 1.76 with trim to 1.75. I thought it odd that the max and trim to were only 0.01 apart.
So I deprimed them and was going to put in tumbler but thought I'd first trim them all to 1.75 since brass was unknown to me.
What I found was that probably close to half the cases measured OAL 1.73-1.74. I expected them to be OVER the 1.75.
Maybe milsurp loads them shorter for better feeding in a AR?
I just found that odd. Excuse the rambling of an old addled man.