Don’t know the answer to your question...but I just bought 9 boxes of Norma Brass in 300 AAC Blackout. Price seemed right to me...25 empties at $7.71 per box. Had planned to buy 10, but once I added other related items the shipping bumped to $13.95, so I dropped one box of brass to get it back to $9.95.
Won’t be loading these anytime soon, so I won’t be reporting on how well they hold up. Still trying to turn the idea of building an AR in 300 Blackout into a semblance of a plan...so when I saw the brass on sale I thought...why not? I had thousands of self fired 9mm in my utility room for nearly two decades before reloading, so having brass around for an eventual purpose isn’t a new thing for me.