US Cartridge, 40mm TP-T, M91
This fixed ammunition resembles the 40mm HE-T cartridge Mk 2 and is used for target practice in 40mm gun cannons.
The projectile, filled with an inert material, simulates the high-explosive service round. The base is fitted with a tracer, and an inert or dummy point-detonating fuze forms the nose. A rotating band encircles the projectile near the base where the projectile is assembled into the cartridge case. The cartridge case is crimped to the projectile and is filled with loose propellant. The base of the case forms an extractor rim and it contains a percussion primer which consists of a perforated tube containing black powder and a percussion element.
Collaborative Ordnance Data Repository