The UmarexÂ® Legends Line is now rocking the legendary M3 Grease Gun. The Legends M3 Grease Gun from Umarex Airguns is based on the M3A1 variation used from 1944 and beyond. Underneath the dust cover resides the bolt and its cut-away thumb charging slot. This blowback action SMG does fire from the open bolt just like the M3 firearms did. Noteworthy features include the collapsible wire stock, drop-free 60 round magazine, fixed peep style sights, and a 1,050 BB per minute rate of fire. Like other Legends SMGs, the M3 Grease Gun is powered by (2) 12-gram CO2 cartridges. Expect to shoot approximately 120 BBs (three magazines) for each full CO2 charge.