This is an original Rear Buffer Sleeve for the 20mm M24A1 Automatic Gun and its naval variant, the Mk16, offered in new old stock condition. Manufactured to U.S. military specifications under Part Number A25565 (also listed as 5025565) and FSN 1005-502-5565, this component is a critical part of the buffer and recoil system found in multiple American 20mm cannon platforms used during the mid-20th century.

The rear buffer sleeve serves as a precision-machined housing for the buffer assembly, absorbing recoil energy during the firing cycle to ensure operational reliability and reduce mechanical stress. These buffer sleeves were used extensively on airborne and naval platforms in both the U.S. Navy and Air Force, notably during the Korean War through Vietnam.

Historical Significance – 20mm M24A1 / Mk16 Guns

The M24A1 and Mk16 20mm cannons were derivatives of the Hispano-Suiza HS.404, adapted by the United States for use in high-rate-of-fire, gas-operated weapon systems on aircraft and shipboard mounts. These guns were used on platforms such as the F-86 Sabre, F9F Panther, and various U.S. Navy riverboats in Vietnam. The Mk16 variant and shared parts interchangeability with the M24A1, including the rear buffer sleeve.

Known for their simplicity, durability, and effectiveness, these cannons played a vital role in American aircraft armament doctrine in the post–World War II period.

Product Details:

Item: Rear Buffer Sleeve
Compatible With: 20mm M24A1 and Mk16 guns
Part Numbers: A25565 / 5025565
FSN: 1005-502-5565
Condition: New Old Stock (NOS)
Function: Houses a recoil buffer spring, which aids in energy absorption during automatic fire

Ideal For:

Restoration of M24A1 / Mk16 weapon systems
Historic aircraft and naval cannon displays
Firearms collectors and U.S. military ordnance historians
Cold War or Korean War reenactment armament setups
Spare part resupply for museums and private inventories

This rare 20mm Rear Buffer Sleeve is a vital piece of American ordnance history, directly supporting the functional and structural integrity of some of the U.S. military’s most widely deployed aircraft and shipboard guns of the Cold War era.

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

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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