The 81mm M29 Mortar - Original U.S. Army 8mm Training Film from 1962 in 4K HD

Published on January 7, 2026
Duration: 22:22

This guide details the expert-level procedure for calibrating and laying the M29 81mm Mortar, as demonstrated in a 1962 U.S. Army training film. It emphasizes precise sight calibration using the M34A2 Sight Unit and M19 Boresight, achieving an 800 mil elevation standard. The process involves establishing aiming points and reference lines with an aiming circle and posts to ensure parallel mortar barrel alignment for accurate fire missions. The instruction highlights the importance of geometric principles and disciplined execution for effective mortar operations.

Quick Summary

The M29 81mm Mortar requires precise sight calibration using the M34A2 Sight Unit and M19 Boresight, starting with 800 mils elevation. Laying involves using an Aiming Circle for azimuth orientation and establishing reference lines with aiming posts for rapid re-engagement, all while adhering to strict safety protocols.

Chapters

  1. 00:00Introduction and Scenario
  2. 01:01Sight Calibration Fundamentals
  3. 01:55Boresight Components and Mounting
  4. 03:06Elevation Calibration
  5. 04:50Deflection Calibration
  6. 07:00Theory of Laying the Section
  7. 10:31Practical Laying Procedure
  8. 13:58Establishing Reference Lines
  9. 15:12Safety and Pre-Fire Checks
  10. 17:28Fire Mission Execution
  11. 18:47Misfire Procedures

Frequently Asked Questions

How is the M29 81mm Mortar sight calibrated according to the 1962 U.S. Army training film?

Calibration begins by setting the sight to 800 mils elevation and zero deflection. A boresight is mounted below the muzzle, and the barrel is adjusted until the boresight's level is centered at 800 mils. The mortar sight's bubble is then centered, and its elevation scale reset to 800 mils.

What tools are essential for laying the M29 81mm Mortar?

Essential tools include the M34A2 Sight Unit for aiming, the M19 Boresight for initial barrel alignment, and an Aiming Circle for orienting the mortar along a specific azimuth or direction of fire.

What is the purpose of establishing reference lines with aiming posts for the M29 Mortar?

Permanent reference lines are established using a far post (100m) and a near post (50m). When aligned, the gunner sees a single sight picture, enabling rapid re-laying of the mortar during active fire missions.

What are the critical safety checks before firing the M29 81mm Mortar?

Safety checks include verifying mask and overhead clearance, ensuring the socket cap is correctly oriented, the barrel is locked to the base plate and bipod, and the spread chain is taut. The bore must also be swabbed.

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