The US Tank Destroyer doctrine was well renowned for its use of turreted self-propelled guns, designated as “Gun Motor Carriage” by the U.S. nomenclature in World War II. The intended role for this anti-tank vehicle design was to quickly adapt to the rapidly mobile battlefield, as well as to intercept, defend, and secure strategic locations against the enemy armored forces. A turret could provide an effective and immediate response against threats from more than just a single direction… even if some vehicles did not totally fit into that description (see the M10 TD and M8 GMC and their manually-traversed turret).

But such a design choice did not deter the U.S. Army Ordnance’s attempt to go on a venture and experiment with building turretless gun motor carriages. Most of them usually ended up as no more than just a single-working prototype to demonstrate their performance in trials. However, few of them made their way into a working interim solution until a proper turreted vehicle could roll out into production. Such an anti-tank vehicle was to be armed with an ancient 3-inch (76.2 mm) anti-air gun on top of a modified M3 Medium Tank chassis. Enter the 3-inch Gun Motor Carriage M9.

Continue reading “Standardized, Never Entered Service: 3-inch Gun Motor Carriage M9” →