This original .50 caliber M3 Trunnion Adapter is a genuine U.S. military component designed for use with the .50 cal M3 aircraft machine gun system. Identified by Part Number 5504052 and National Stock Number (NSN) 1005-00-550-4052, this adapter serves as a critical mounting interface between the receiver and trunnion block, providing the necessary alignment and secure support for the M3 machine gun in aircraft.

The M3 .50 caliber machine gun—developed during World War II and refined throughout the Cold War—was an advanced version of the ANM2 Browning, designed to provide a higher rate of fire (up to 1,200 rounds per minute) for use in aircraft-mounted roles. It was widely deployed on U.S. fighters and bombers such as the F-86 Sabre, F-84 Thunderjet, and early helicopter platforms.

This trunnion adapter is ideal for collectors, restorers, and museum-grade display builders working with M3 aircraft gun installations or ground conversion projects.

Product Specifications:

Condition: New Old Stock (NOS)
Part Number: 5504052
FSN: 1005-550-4052
NSN: 1005-00-550-4052
Material: U.S. mil-spec steel
Compatibility: .50 caliber M3 machine gun systems
Function: Adapts and mounts receiver to trunnion block or support structure

Historical Significance:

The .50 cal M3 machine gun marked a leap forward in U.S. aerial and vehicular firepower. Used from WWII through the Cold War era, the M3 was preferred for its increased firing rate, which is essential for engaging fast-moving aerial threats. The trunnion adapter allowed for secure mounting in demanding combat environments, playing a vital role in the reliability and versatility of the M3 system across various platforms.

Ideal For:

Restoration of vintage .50 cal M3 machine gun systems
U.S. aircraft armament display setups
Military museum curators and reenactors
Collectors of Cold War aircraft and weapon system components
Armorer and surplus part inventories

Approx length 4", Approx width 3", Approx height 2", Approx weight 1.4lbs.

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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