The Galleries
- Robert E. Petersen Collection
- Ancient Firearms - 1350 to 1700
- Road to American Liberty - 1700 to 1780
- A Prospering New Republic - 1780 to 1860
- A Nation Asunder - 1861 to 1865
- The American West - 1850 to 1900
- Innovation, Oddities and Competition
- Theodore Roosevelt and Elegant Arms - 1880s to 1920s
- World War I and Firearms Innovation
- WWII, Korea, Vietnam and Beyond - 1940 to Present
- For the Fun of It
- Modern Firearms - 1950 to Present
- Hollywood Guns
M.A.S. Model 1938 Submachine Gun
This blowback-operated submachine gun employs some unusual features. Among these are a folding trigger which, when pushed forward, acts as a safety mechanism. The stock is also removable, and the gun cannot be fired under this condition. In addition, the bolt travels at an angle relative to the plane of the barrel. Roughly equivalent to a .32 ACP cartridge, the 7.65 mm MAS caliber ammunition used in this gun is now obsolete. During its service life, it was only manufactured at arsenals in France and Vietnam.