Me either, not in .223. Especially not of the same brand. I've gotten a 10 gr spread between different headstamps, but not the same headstamp. I suspect that you were weighing brass that was untrimmed, and perhaps a case or three of differing headstamp got mixed in your lot.
"Always place your clothes and weapons where you can find them in the dark"
"Understand that the enemy is not the enemy in his own eyes ;this may offer you an opportunity to make him your friend. If not, you can kill him without hate, and quickly."