- 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
Winchester Model 21 Shotgun - 20 ga.
An American classic, the Winchester Model 21 side-by-side shotgun was a regular choice for many hunters and shooters. This example bears the signature of Robert E. Petersen in gold on its triggerguard.