As there is no mention of an antitank weapon of lesser power than the Sabot rocket, LAW rocket or RPG-7 known as a "mangler", some liberties must be taken when describing this weapon. As it of lesser strength and accuracy at distance than the Sabot, LAW or the RPG, it must be assumed that the guidance systems and warhead are of lesser grade, perhaps improvised post-war manufacture. As it is of slightly lesser strength than a tossed chunk of TNT, let alone a Grenade, there is room for debate as to what kind of improvised warhead it packs: it certainly lacks the punch of its high-end brethren!
As it technically uses the same skill as those of its idols, the wannabe tank killer earns the name. It's better thought of as a stand off Grenade, with less of a punch. Use these up against foes at medium to short range to build up your AT weapon skills. Pick large groups if possible!
Against less resistant obstacles, the mangler can be used to breach doors. Then again, so can a Crowbar in some cases!