If you don't have a good supply...
I just did a quick check of some of my favorite suppliers. The places that listed my favorite powders, primers, and bullets as in stock 7-10 days ago now list them all as Out of Stock or Back-Ordered. The panic has set in. 2 weeks ago I could've bought .223 in 1,000 round lots. Today, not even one .223 round or the parts to build a round can be found (easily).
Panic has set in and it's far worse than four years ago...
Glock Certified Armorer