round in the chamber will still be ready to fire, and must be manually ejected. Uses Closed-bolt designs are often used in rifles. The improved accuracy of closed-bolt weapons is more desirable, while the poorer heat dissipation is less of an issue for slower-firing weapons. In contrast, open-bolt designs are more often used in automatic weapons, such as machine guns. For fast-firing automatic weapons, heat will rapidly build up from sustained firing, but accuracy is of less importance. Thus, the improved heat dissipation of open-bolt designs is generally more desirable in automatic weapons. Closed-bolt firearms Examples of closed-bolt firearms include: AR-15 style rifle Armalite AR-10 Armalite AR-18 FAMAE SAF FN F2000 Heckler & Koch MP5 Heckler & Koch UMP Heckler & Koch G3 Heckler & Koch G36 Heckler & Koch HK21 Kalashnikov rifle Madsen machine gun Maxim gun Mendoza HM-3 MG 08 MG 13 MG 17 machine gun MG 131 machine gun M2 Browning machine gun M16 rifle M1895 Colt–Browning machine gun Parabellum MG14 SIG 550 Spectre M4 Steyr AUG Vickers Machine Gun Mixed mode firearms Examples of mixed mode firearms (capable of operating from either an open bolt or closed bolt) include: CETME Model A FG 42 FN SCAR - Heat Adaptive Modular Rifle LWRC Infantry Automatic Rifle - M6A4 M1941 Johnson machine gun See also Action (firearms) References External links How Does it Work: Open Bolt vs Closed Bolt Firearms Firearm actions