Fig. 1: showing the Thompson M1A1 sub-machine gun around which the pulse rifle is built. Note the 20-round magazine, which will be attached to the fake magazine butt-plate. Here the wooden stock and foregrip have already been removed. The rear sight will be removed, the barrel replaced and extended, and the wooden grip replaced with a cast one.
Fig. 2: showing the Remington 870 shotgun which acts as the grenade launcher. The shotgun is almost invisible in the finished pulse rifle, except for the ejection port (here bright silver). Note how the shotgun trigger corresponds with the space below the ammunition counter; this is where the 'grenade' trigger would be. In this diagram the shoulder stock has already been removed. The fore-end of the barrel will be cut down and the wooden grip removed.
Fig. 3: the visible surface of the grenade launcher is actually the outer casing of a Franchi SPAS-12, reversed so that it points backwards. This conceals the shotgun. An elliptical hole needs to be milled out of the right-hand side, which will exactly match the shotgun port within. This will allow the shotgun cartridges to be ejected. Also a hole must be cut in the underside, matching the loading port of the shotgun.
Fig. 4: this is the pump-grip from the Franchi. (Note that it is facing the correct way; in other words it is reversed on the Franchi casing.) The grip will be sawn down by about half its length (see faint white mark), and a cutout made on the right side so as not to interfere with the cartridge ejection as the pump slides back. On the left side a small plate is riveted through to the pump of the Remington inside; thus the two are locked together and the Franchi grip actually works the Remington slide.
The above gun components form the majority of the pulse rifle. The only parts remaining to be custom-made are:
Pulse rifle background and reproductions