A variation of towed is portee, wherever the motor vehicle carries the gun that is dismounted for firing. Mortars will often be carried in this way. A mortar is typically carried in an armored auto and may both fire from it or be dismounted to fire from the ground. https://imr-432058013.get-blogging.com/17485070/the-ultimate-guide-to-hodgdon-h4350-smokeless-powder