Bushmaster Arm Pistol 5.56mm NATO Bullpup, Semi-Auto, 11.5 in Barrel, Parkerized, 1970s–1980s Production
This Bushmaster Arm Pistol stands out for its compact bullpup layout, long-stroke gas piston system, and compatibility with STANAG/AR-15 magazines. Produced in limited numbers during the 1970s–1980s, it reflects an early and historically notable Bushmaster design inspired by the Colt IMP-221 concept. Factory specs include an 11.5 inch barrel, approximately 20 inch overall length, and about 4.25 lb weight, all in a parkerized steel build with an alloy shroud.
Condition
Overall Condition: Good condition, showing some signs of prior use and handling.
Bore Overall Condition: Good - Clean, well-maintained, minor wear marks.
Bore Rifling: Good Rifling - Intact, well-defined lands and grooves.
Specific Condition Notes: This firearm is in solid shape. There are scratches and blemishes present. The bore is clean and shiny. There is minor rust formation on the charging handle.
What's Included
- 1x 20-round USGI-pattern aluminum STANAG magazine (straight-body)
The Arm Pistol uses a bullpup layout with the magazine well behind the pistol grip, keeping overall length down without shortening the action. It operates via a long-stroke gas piston with a rotating bolt and features right-side ejection. The two-position safety selector provides Safe/Fire settings, and push-pin fasteners support quick takedown.