Description
Add an original piece of U.S. military fire-control history to your collection with this M1 Gunner’s Quadrant. This portable precision level was used to measure, set, and verify the vertical angle of a weapon.
The M1 Gunner’s Quadrant was a general-purpose fire-control tool used with many U.S. guns, howitzers, antiaircraft guns, tanks, self-propelled weapons, and heavy artillery systems.
What This Tool Does
The M1 Gunner’s Quadrant helped crews set or check a weapon’s elevation. The required angle was set on the quadrant before the tool was placed on the weapon. The weapon was then moved until the bubble was centered, indicating that it had reached the selected angle.
The quadrant could also be used to measure a weapon’s existing angle independently of its built-in sight or elevation indicator.
Common Military Uses
- Setting gun elevation
- Checking gun depression
- Verifying built-in elevation devices
- Boresighting
- Aligning sights and telescopes
- Performing fire-control checks
- Inspecting weapons
- Supporting field maintenance
- Emergency elevation pointing
Technical Details
The M1 features a sector-shaped frame with a spirit level, pivoting arm, micrometer adjustment, hardened contact shoes, and LINE OF FIRE direction arrows.
- Scale: 0 to 800 mils on one side
- Reverse scale: 800 to 1,600 mils
- Coarse settings: 10-mil increments
- Micrometer markings: 0.2-mil increments
- Full quadrant: 1,600 mils, equal to 90 degrees
Historical Significance
The M1 Gunner’s Quadrant was in U.S. Army service by World War II and remained useful for many years. Its simple, durable design required no electrical power.
Gun crews and maintenance personnel used tools like this to lay weapons, check sights, test mounts, and identify errors in elevation mechanisms and fire-control equipment. It represents the hands-on methods used to achieve artillery accuracy before modern digital systems.
Key Features
- Original U.S. military M1 Gunner’s Quadrant
- Portable precision leveling instrument
- Measures weapon elevation and depression
- General-purpose fire-control tool
- Scale covers 0 to 1,600 mils
- Fine micrometer adjustment
- Marked with LINE OF FIRE direction arrows
- Suitable for display, study, or restoration reference
Approximate Dimensions
- Length: 7 inches
- Width: 6 inches
- Height: 1 inch
- Weight: 2 pounds
What Is Included
This listing is for one M1 Gunner’s Quadrant. No weapon, howitzer, tank, mount, case, tools, manual, or additional items are included unless specifically shown or noted.
Ideal For
- U.S. artillery collections
- Gunner’s quadrant collections
- Fire-control equipment displays
- World War II field gear collections
- Cold War ordnance collections
- Tank and howitzer restoration references
- Museum and archive displays
- Military tool collections
Product Images
Pictures are stock images of our inventory. Unless otherwise noted, you will not receive the exact item shown. The pictures represent the general condition of the available inventory. The item you receive may be in slightly better or worse condition than the example shown.
Please review our Order Lead Times page before placing your order.