M41-A Pulse Rifle Counter and Sound Unit

Jim Shima has informed me of the following replica parts he has available. If you would like to get more information about these parts, please visit his site. Images below are © Jim Shima, and used here with written permission.

The ALIENS Pulse Rifle is arguably one of the most practical and believable Sci-Fi movie guns of all times. What gave it this mystique is the fact that all of the Sci-Fi features of it had an actual purpose. The most prominent of these features is the ammo counter. With it's ability to instantly show how well armed the Marines were, it even served as a plot point for the movie. As tends to be true with the most interesting of features of a replica, it is also quite likely the hardest feature of the Pulse Rifle to reproduce in working form. Jim Shima has taken care of that problem for us. He has produced a working counter that does a fantastic job of replicating the original.

Construction:
The standard unit has two leads (red and black) coming off which are the trigger/switch wires. It has two more leads (red and white) coming off which are connected to the battery holder. The unit runs on two AA batteries. There are two terminals which do not have leads attached. These are for connection to Jim's Vortex device which can be used to simulate the sound of the Pulse Rifle firing. There are holes for mounting on two opposing corners.

Operation:
The unit is activated by placing two AA batteries in the tray attached to the red and black leads. On activation, the counter goes to 99 and drops down to 95. This happens fast enough, that you have to really look for it to see it happen. When the red and white trigger wires are connected, the counter drops by one for a short contact, and it will continue to count down at a preset rate if they are held together for a prolonged period. Once the counter reaches 0, it will stay there until it is reset. Removing and replacing the batteries will cause the counter to reset. The deluxe version includes lights which can be placed in the barrel. These lights work in conjunction with the counter to give an additional effect of firing.

Incorporation:
There will obviously need to be some modification to incorporate the counter into a Pulse Rifle, but they are not overly difficult. The main changes are going to be to build the battery holder into the clip so that removing and replacing the clip will cause the counter to reset, and to connect the activation wires to the trigger to activate the counter. Both of these changes can be made with some simple soldering.

Update - March 15, 2001

Jim has added even more features to an already great product. He has converted the counter to work off of a single 9V battery, rather than the previous double AA batteries. Also, the deluxe version of the Pulse Rifle counter is now available with either red or white LEDs to simulate the muzzle flash as the counter ticks down.

There is also a sound board available now. Previously, sound could be added to the counter through the use of his Vortex sound unit. However, this new sound board is Pulse Rifle specific and significantly cheaper. It has several built in sound clips of the Pulse Rifle Firing. When wired in to the counter unit, it will randomly combine these sounds to match the duration that the trigger is activated. When the counter reaches 0, there is a looping sound clip of the gun dry firing that will play. The sound board will work off of the same 9V battery supplying power to the counter. If you have the older 3V version of the counter, you will need to get the new 9V version to use this sound card.

For more information about this great product and the Vortex sound unit, check out Jim Shima's site, Hyperdyne Labs.