Description
Technical Manual (TM 9-1005-246-24) for 20mm M139 Automatic Gun November 1971 FSN 1005-999-0896
Add a strong piece of Vietnam War-era / Cold War armored vehicle armament documentation to your collection with this Technical Manual TM 9-1005-246-24 for the 20mm Automatic Gun M139, dated November 1971 and listed with FSN 1005-999-0896.
Historical Significance
The 20mm M139 Automatic Gun is closely associated with the U.S. Army’s Cold War reconnaissance vehicle program. The M139 was the U.S. service designation connected to the Hispano-Suiza HS.820 / Oerlikon KAD 20mm autocannon family, with reference data identifying M139 as the U.S. service designation and listing the weapon family as a 20x139mm autocannon.
The M139 became especially important on the M114A2 Command and Reconnaissance Carrier, where it was mounted in the powered XM27 cupola. That arrangement gave the reconnaissance vehicle a major firepower upgrade over earlier machine-gun-only configurations, while allowing the commander to engage targets from a protected position.
This November 1971 manual belongs to the period when the Army was documenting the maintenance, support, and parts side of the M139 system. For collectors, it connects directly to the technical world behind Cold War armored reconnaissance vehicles, powered cupolas, and vehicle-mounted 20mm automatic cannon systems.
The 20mm M139 Automatic Gun
The M139 represented the Army’s move toward heavier automatic cannon armament on reconnaissance and armored vehicle platforms. Instead of relying only on .30 caliber, .50 caliber, or 7.62mm machine gun fire, the M139 gave selected vehicles a 20mm weapon system suited for reconnaissance support, suppressive fire, and engagement of light targets.
Reference data for the HS.820 / M139 family lists features including 20x139mm ammunition, belt-feed capability, and a listed rate of fire of 1,000 rounds per minute. Those technical characteristics help explain why the system was suited to a powered cupola installation on a reconnaissance vehicle.
This manual is especially relevant to collectors focused on:
- 20mm M139 Automatic Gun documentation
- M114A1E1 and M114A2 armored reconnaissance vehicles
- XM27 powered cupola systems
- 20mm autocannon maintenance and parts research
- Vietnam War-era armored vehicle displays
- vehicle-mounted automatic cannon collections
What This Manual Covers
As TM 9-1005-246-24, this publication served as a maintenance and parts-reference manual for the 20mm M139 Automatic Gun at organizational, direct support, and general support levels. Manuals like this were official working documents, intended to support identification, use, servicing, and field support of the equipment they covered.
This manual is especially useful for:
- M139 automatic gun identification and maintenance reference
- repair parts and special tools research
- XM27 cupola and M114A2 armament documentation
- U.S. Army ordnance technical manual collections
- museum and archival reference libraries
- collectors completing an M114 / XM27 / M139 technical manual set
Key Features
- Technical Manual TM 9-1005-246-24
- Covers the 20mm Automatic Gun M139
- Dated November 1971
- Listed with FSN 1005-999-0896
- U.S. Army organizational, direct support, and general support maintenance subject
- Includes repair parts and special tools list context
- Connected to the M114A2 Command and Reconnaissance Carrier
- Associated with the XM27 powered 20mm gun cupola
- Strong Vietnam War / Cold War armored vehicle armament collector subject
- Excellent reference for M139, XM27, M114, and 20mm autocannon collectors
About This Manual
This listing is for Technical Manual TM 9-1005-246-24, covering the 20mm M139 Automatic Gun, dated November 1971, with FSN 1005-999-0896.
This listing is for the manual only unless otherwise stated. No automatic gun, cannon, cupola, armored vehicle, ammunition, tools, repair parts, storage case, or additional accessories are included unless specifically shown or noted.
Ideal For
This manual is a strong fit for:
- 20mm M139 Automatic Gun collectors
- M114A1E1 and M114A2 vehicle reference collections
- XM27 powered cupola displays
- Vietnam War armored vehicle collections
- Cold War U.S. Army technical manual collections
- 20mm autocannon reference libraries
- U.S. Army ordnance manual collectors
- museum and archival reference displays
Approx length 11", Approx width 8", Approx height .25", Approx weight 1lbs.
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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