Description
U.S. Army Technical Manual TM 9-1290-200-14&P for M1A1 and M1A2 Gunner’s Fire Control Quadrants, April 1975
Item Overview
This official U.S. Army reprint covers the M1A1 and M1A2 Gunner’s Fire Control Quadrants. Published as TM 9-1290-200-14&P in April 1975, this copy includes the current replacement pages from Changes 1 and 2. It covers the M1A1 under NSN 1290-00-891-9999 and the tritium-equipped M1A2 under NSN 1290-00-169-1937. This listing is for the technical manual only. It does not include a quadrant, carrying case, artillery piece, vehicle, weapon, or other equipment.
Official Reprint
This copy preserves the April 1975 base manual while incorporating updated pages from Changes 1 and 2. Replacement pages were issued to correct information, revise procedures, update parts data, and add current safety or maintenance guidance. An official reprint placed these pages into one working publication so personnel did not need to update the manual by hand.
Publication Details
This manual was prepared for operators, unit personnel, and maintenance specialists responsible for using and supporting the M1A1 and M1A2 quadrants.
- Manual number: TM 9-1290-200-14&P
- Publication date: April 1975
- Models covered: M1A1 and M1A2
- M1A1 National Stock Number: 1290-00-891-9999
- M1A2 National Stock Number: 1290-00-169-1937
- Manual type: Operator through general support maintenance
- Additional coverage: Repair parts and special tools list
- Updates included: Changes 1 and 2
- Issuing authority: Headquarters, Department of the Army
- Country of origin: United States
- Item included: Technical manual only
Manual Coverage
The “14&P” suffix identifies a combined publication covering operation, unit care, direct support, general support, repair parts, and special tools. Its subject matter includes handling, inspection, cleaning, preventive maintenance, troubleshooting, calibration, and serviceability testing. Illustrated parts information helped personnel identify and order authorized components. Test procedures included micrometer checks and end-for-end checks used to find measurement errors before the quadrant was placed in service.
About the M1A1 and M1A2 Quadrants
Both models are portable precision instruments used to measure or set the elevation and depression of a weapon. Their main parts include a graduated radial arm, micrometer adjustment, level vial, and low- and high-angle shoes. The crew places the quadrant on prepared seats or a leveling surface and moves the weapon until the bubble is centered. The M1A2 retained the basic operation of the M1A1 but added a tritium light source and radioactive warning markings for low-light use. These model names identify gunner’s quadrants and are not references to M1A1 or M1A2 Abrams tanks.
Role in Fire Control
Correct gun elevation is essential because a small angle error can move an artillery round far from its intended target. These quadrants allowed crews to apply an ordered quadrant elevation, measure a gun tube’s angle, level a cannon, and check mounted elevation instruments. Their mechanical operation also provided an independent reference when testing optical, mechanical, or electronic fire-control equipment.
Weapon-System History
The M1A1 and M1A2 were general-purpose instruments rather than components of one weapon system. Variants of the quadrant were used with towed howitzers, self-propelled artillery, tanks, mortars, antiaircraft mounts, and other cannon systems. Documented applications across their service life included the M101A1 and M102 105mm howitzers, M109 155mm self-propelled howitzer, M110 8-inch self-propelled howitzer, M551 Sheridan, M728 Combat Engineer Vehicle, and M163 Vulcan Air Defense System. Later artillery systems continued to use the same type of quadrant for checks and alignment.
Historical Background
Gunner’s quadrants developed from much older tools used to measure cannon elevation. The American M1 family was established during World War II and continued to develop through the Cold War. The M1A1 refined the proven mechanical design, while the M1A2 added tritium illumination for night and low-light work. This April 1975 manual dates from a period when the Army operated older mechanical sights beside newer electronic fire-control systems.
History of Use
Artillery and armored-vehicle crews used these quadrants during firing missions, boresighting, tube leveling, weapon alignment, maintenance inspections, and training. Maintenance personnel also used them to verify mounted elevation quadrants, telescope mounts, and related sighting equipment. The simple and accurate design remained useful for decades because it required no external electrical power and could support many different weapon platforms.
M1A2 Tritium Safety
The M1A2 contains a sealed tritium light source associated with its level-vial assembly. Tritium allowed the instrument to be read under low-light conditions without an external lamp. Army procedures required personnel to observe radioactive-material warnings and report a damaged or broken light source through the proper safety channels. This manual is a historical publication and does not include an M1A2 quadrant or any radioactive equipment.
Collector and Research Value
TM 9-1290-200-14&P is a useful reference for collectors, restorers, museums, and historians studying American artillery instruments. Its combined operating, maintenance, parts, and safety information documents how both quadrant models were supported during the 1970s. The incorporated change pages also make this official reprint a more complete working reference than an unmodified base issue.
Condition
This vintage military technical manual may show cover wear, edge wear, folds, yellowing, stains, writing, stamps, punched holes, loose pages, or other signs of age and storage. Printing details and condition may vary between available copies. Please check the pictures for the general condition of the item.
Ideal For
This manual is well suited for collections, restoration projects, research libraries, and displays focused on artillery, military instruments, and Cold War fire-control equipment.
- U.S. Army technical-manual collections
- M1A1 and M1A2 Gunner’s Quadrant research
- Artillery fire-control displays
- Military instrument restoration
- Cold War equipment exhibits
- Museum and archival collections
Approx length 8", Approx width 11", Approx height .25", Approx weight .5lbs.
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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