Ammo and mags. AR-15s and Glock 9mm really shines here.
True, and I have a Glock 26 with lots of 10 round magazines, and a few 15 round G19 mags.
I am very light on my AR magazines, however, and you remind me that I need to build up my magazine and 5.56mm ammo reserves.
Last gun show I was at I got several PMag gen2 30 rounders, in the package, for $10 each. I kick myself for not buying more.