Not to mention that modern defensive ammo has 50% expansion, so a 9mm round (.355) will enlarge to .5325.
Larger than the sacred .45
Well the Sig or Hornady defensive rounds for a .45 expand to well over 17 mm from 11.5.
Mine is bigger than yours 😉
Oh, also there’s 1 in the chamber and 10 in the mag, plus an extra 10 rnd mag for my walk-in-the-woods kit. Sig P220 full frame.