[legion]

First off, my AR-15 is chambered for 5.56mm NATO, so shooting either 5.56mm or .223 Rem is not an issue for the rifle.

I bought some used brass at the gun show yesterday. It was all supposed to be all Remington brand .223, but once I opened the packs, I found them to be a mix of brands with some .223 and some 5.56. I did check the packs at the show, but they were vacuum-sealed and seemed to be all the same brand/caliber there.

My question, is, can I reload the 5.56 brass with my .223 dies. It's my understanding that the only difference between 5.56 and .223 is that 5.56 has a longer neck. I was thinking that if I trimmed all of the 5.56 cases to .223 standards, then I would eliminated the difference and be able to reload the cases with .223 dies.

Thoughts?