scope:

This specification supports the acquisition of the Cannon, 155MM Howitzer: M1A1 and M1A2 consisting of the tube and the breech mechanism. This specification includes the minimum essential Engineering and Packaging Requirements and the necessary Quality Assurance Provisions to determine that these requirements have been met.

The two howitzer cannon are classified as follows:

Type I. Cannon 155MM Howitzer: M1A1 with a rifling twist of 1 turn per 25 calibers and is only used with the 155MM M114A1 towed medium howitzer system.

Type II. Cannon 155MM Howitzer: M1A2 with a rifling twist of 1 turn per 20 calibers and is only used with the 155MM M114A2 towed medium howitzer system.

This specification is subject to the is of QSTAG-57, Howitzer, 155MM, M1A1; Carriage, Howitzer, 155MM, M1A2 with ammunition and fire control equipment. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commander, Armament Research, Development and Engineering Center, US Army Armament, Munitions and Chemical Command, ATTN: SMCAR-CCB-SAS, Watervliet, N.Y. 12189-4050 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter.

intended Use:

The 155MM M1A1 cannon is intended for use with the M114A1 towed medium howitzer system and the 155MM M1A2 cannon is intended for use with the M114A2 towed medium howitzer system.