Abstract: This invention concerns a training simulator comprising a simulated gun, constructed mainly from machine-welded components and mechanisms, and which simulates a breech jacket, breech and breech wedge, and also comprising simulated ammunition, consisting of the assembly of a shell and a case, with means of connecting them together, and which are separated by applying pressure on the case in the same way as a detonator hammer.When simulated firing occurs, the breech recoils on roller slides, under pressure from a hydraulic jack. A mechanism fixed to the breech raises the breech wedge by means of a first spring, and transmits to the breech-opening lever, through this spring and a second spring, a force of resistance equal to the force actually applied by the gun-loader to open the breech.The purpose of this simulator is to train tank crews in the various procedures of a firing sequence.