Shockbottle 100-Hole 9mm Chamber Checker Cartridge Case Gauge. The Shockbottle Chamber Gauge is ideal for reloading and shooters who want to ensure better reliability of their ammo in chambering and extracting. The Chamber Gauge is machined from aircraft grade aluminum and hard anodized using S.A.M.M.I. spec's. This Chamber Gauge is specifically designed to utilize a 100 round ammunition box as a "flip-tray", then can be flipped into an ammo box bullet down and ready for the range.