4.5mm BB's

The Milbro Speedmaster magazine is a multishot, cassette-style magazine for the Milbro Speedmaster CO2 air rifle, designed to hold 10 pellets in .177 caliber or 9 in .22 caliber. It allows for rapid reloading by simply dropping pellets into the open slots until full, with the rifle's bolt action then cycling a pellet into the barrel from the magazine. Spare magazines are available to minimize downtime between shots.