This new old stock 20mm M39 Operating Slide Rammer (Right Hand) is an authentic U.S. military surplus part designed for the M39 revolver cannon, a widely used autocannon developed in the 1950s for high-performance fighter aircraft. Identified by Part Number 8400335-B and National Stock Number (NSN) 1005-00-039-4991, this right-hand rammer assembly is a critical component in the loading cycle of the cannon, responsible for advancing each round into the chamber during high-speed firing operations.

The M39 cannon was originally developed by the Springfield Armory and quickly became standard armament on early Cold War U.S. jet fighters, including the F-86 Sabre, F-100 Super Sabre, and F-5 Freedom Fighter. Firing 20×102mm ammunition at a rate of up to 1,500 rounds per minute, the M39 was renowned for its reliability and precision in air-to-air and air-to-ground missions. This operating slide rammer played a key role in maintaining that performance by ensuring consistent, rapid chambering of each round.

Product Specifications:

Condition: New Old Stock (NOS)
Orientation: Right Hand
Part Number: 8400335-B
NSN: 1005-00-039-4991
Compatibility: 20mm M39 aircraft revolver cannon
Application: Feeding/Ramming system component

Historical Significance:

The M39 cannon was the first successful American adaptation of a revolver cannon design, modeled after German WWII-era Mauser designs and tailored for the faster speeds and combat requirements of jet-powered aircraft. Its implementation marked a significant leap in firepower and rate of fire for tactical U.S. aircraft. The 8400335-B right-hand operating slide rammer is an essential component of this proven weapon system and a valuable find for collectors, restorers, and armament historians.

Ideal For:

Restoration projects involving M39 revolver cannons
Aviation museums and static display restoration
Armorer inventories for Cold War-era aircraft systems
Collectors of U.S. military aviation ordnance
Educational or film industry prop resources

Add this rare NOS 20mm M39 Operating Slide Rammer (Right Hand) to your collection or restoration project and own a tangible part of Cold War aerial firepower history.

Approx length 5", Approx width 5", Approx height 1", Approx weight 1.2lbs.

Pictures are stock images of our inventory. Unless otherwise noted, you will not be receiving the exact item shown in the pictures. The pictures are representative of the item's general condition. The item you receive might be slightly better, or worse, condition than was shown in the pictures.

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