Description
U.S. Army Technical Manual TM 9-1290-262-12P for M2 Aiming Circle, February 1959
Item Overview
This U.S. Army technical manual is the basic issue items, repair parts, and special tools list for the M2 Aiming Circle. Published as TM 9-1290-262-12P in February 1959, it supported military personnel responsible for maintaining and supplying this precision artillery instrument. This listing is for the technical manual only. It does not include an aiming circle, tripod, carrying cover, instrument light, plumb bob, weapon, or other equipment.
Publication Details
This Cold War publication documented the parts and supporting equipment required to keep the M2 Aiming Circle available for field service.
- Manual number: TM 9-1290-262-12P
- Publication date: February 1959
- Official title: Basic Issue Items, Repair Parts, and Special Tools List for Circle, Aiming, M2
- Equipment: M2 Aiming Circle
- Later National Stock Number: 1290-00-614-0008
- Manual type: Basic issue items, repair parts, and special tools list
- Issuing authority: Headquarters, Department of the Army
- Country of origin: United States
- Item included: Technical manual only
Manual Coverage
The “12P” suffix identifies this as a parts publication supporting operator and organizational maintenance. It helped personnel identify authorized components, replacement parts, accessories, and special tools associated with the M2 Aiming Circle. This is primarily a parts and supply reference rather than the complete operating or field-and-depot repair manual.
About the M2 Aiming Circle
The M2 is a portable optical and mechanical instrument used to measure precise azimuth and elevation angles from a selected reference line. It combines an elbow telescope, magnetic compass, leveling controls, graduated scales, and micrometer adjustments. Artillery and mortar crews used these features to establish direction, measure angles, and align several weapons on the same firing azimuth.
Equipment Features
The M2 has a four-power, fixed-focus elbow telescope with a 10-degree field of view. Its azimuth scale covers a complete 6,400-mil circle, while micrometer controls allow fine adjustments. Circular and tubular levels help the operator place the instrument in a true level position. The M2 can measure up to 800 mils of elevation and 400 mils of depression.
- Telescope: Four-power, fixed-focus elbow type
- Field of view: 10 degrees
- Azimuth rotation: Unlimited
- Maximum elevation: 800 mils
- Maximum depression: 400 mils
- Common tripod: M24 Aiming Circle Tripod
- Lighting equipment: M51 Instrument Light
Role in the Weapons System
The M2 Aiming Circle was common fire-control equipment rather than a component of one specific weapon. In an indirect-fire unit, it helped place howitzers, guns, or mortars parallel to an announced direction of fire. During reciprocal laying, the aiming-circle operator exchanged angle readings with each weapon crew until the sights and weapon tubes were correctly aligned. The instrument could also support basic topographical surveying and the measurement of angles to ground or aerial targets.
Historical Background
The M2 was firmly established in Army service by the mid-1950s, when TM 9-6166 covered its operation and organizational maintenance. This February 1959 parts manual followed as a supply reference, and a separate field-and-depot maintenance manual appeared in 1960. These publications reflect the Army’s effort to standardize the care of precision optical equipment during the early Cold War.
History of Use
The M2 supported artillery and mortar units during the Cold War and Vietnam era. Crews used it when setting up firing positions, checking weapon alignment, establishing grid or magnetic direction, and preparing coordinated indirect fire. The later M2A2 increased the available elevation range, but the original M2 remained important enough to appear beside the M2A2 in Army manuals for many years.
Collector and Research Value
TM 9-1290-262-12P is a useful reference for identifying early M2 Aiming Circle parts and accessories. It also documents Army maintenance, surveying, and indirect-fire practices from the late 1950s. The manual is well suited for military-optics collections, artillery research, museum displays, and restoration projects.
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 a specialized reference for collectors, restorers, museums, and researchers interested in American artillery surveying and fire-control equipment.
- U.S. Army technical-manual collections
- M2 Aiming Circle restoration projects
- Cold War artillery research
- Mortar and indirect-fire displays
- Military surveying-equipment collections
- Museum and archival reference libraries
Approx length 8", Approx width 10", Approx height .1", Approx weight .15lbs.
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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