How To Upgrade Your Light Gun to Arcade Quality

Note from racketboy: Thanks to skate323k137 for sharing this information and letting us republish the information from this forum thread.

No matter if you take your light gun games seriously or you need all the help you can get when it comes to hitting your targets, its always nice to have a high-quality light gun that can rival those at the arcades.

Unfortunately, even a brand new un-modified Sega Saturn light gun will miss a decent percentage of your trigger pulls. I know this because I was actually able to acquire and test several previously un-opened light guns over the past few years. Sometimes the new ones were even worse than used ones (!).

However, once you install a “real”, arcade-quality switch, the end result is a much more consistent response from the gun, and the possibility of a much higher rate of fire. So, now that I can play all my games, I dug out a couple of my spare light guns and went to town installing Cherry brand microswitches (the same switches under the buttons at your local arcade, aka the ones from HAPP Controls).

This post explains how to easily install an arcade quality switch into a Sega Saturn light gun. I made a couple of these in the past and figured some other people might enjoy having arcade quality trigger response at home. Honestly, if you know anyone that works at your local arcade, they’ll probably give you a few microswitches for next to nothing, if not free.

NOTE: This is really a simple mod, but I’ve tried to spell it out so that anyone can follow these instructions. Honestly, a picture of the finished product is all most people would probably need. Obviously, I accept NO RESPONSIBILITY if you screw this up.

What You Need

• (1) Sega Saturn stunner brand name light gun
• (1) Small phillips head screw driver to dis-assemble the gun, and a bigger phillips screw driver to mount the switch.
• (1) Diagonal cutters (wire cutter)
• (1) 25W (recommended) Soldering Iron, Solder, and basic soldering skills
• (1) Cherry brand (recommended) microswitch, with metal actuator piece
• (1) Piece of speaker wire, approx 3-4 inches in length
• (1) Sheet metal screw with a 1/4″ head (5/8″ long, usually also slotted for screw drivers. I used some that came with a cable TV splitter) OPTIONAL BUT HIGHLY RECOMMENDED
• (1) Roll duct tape (you’ll see, especially if you can’t find a suitable screw)
• (1) Small drill bit to pilot the screw hole, i used a 5/64″.
• and of course a drill with which to use said bit.

The Modification Process on the Sega Saturn Light Gun

1. Lay the gun on its side, screws facing up. Remove the screws, and open the gun. If the screws give you a hard time, use one hand to push down on the screw driver and your free hand to grasp the driver with a pliers and turn it. BE SURE TO SET ASIDE THE LENS THAT FITS IN THE END OF THE “BARREL”. (I always lose that &*$@in thing) Also, be cautious not to lose the parts for the “start” button.

2. Use your diagonal cutters to cut the trigger (you can remove the trigger to do this), so it no longer actuates the stock switch. (Not pictured: Trim the metal actuator on the end of the microswitch you’re installing to be flush with the end of the switch)

3. Fire up your soldering iron, and solder one end of the speaker wire to the PCB as shown. You can remove the PCB from the gun while doing this. I just lift it out of the slots, and tilt the top of the board toward me so I can solder to it. For some reason, there are four solder points for the switch, but you only need to use two. (If you were pointing the gun toward something, it would be the two right hand solder points on the switch.)

4. Solder to the Microswitch. since we’re simply shorting a circuit here, the only thing that matters is that you use the NO (normally open) side of the switch, and the ground. You can see where the switch will end up here

5. Lay some duct tape under the switch. I suppose if you had thin window insulation that it may work. The idea here is to line the metal flipper on the switch up with the trigger. It sits too far into the gun without some help. you can see the spot to drill for a screw here too.

6. Put in a screw. or, put in some padding on the other side of the switch. be warned your switch may go out of line if it’s not snug, so i recommend securing it as best you can. The ground post of the switch should be braced against a piece of plastic (in relation to trigger pull) as shown. Also see picture for screw length reference.

7. Make sure everything is in place, the PCB is in the slots, lens and trigger in place, start button in place, wires are out of the way of screw holes, etc. When you’re done, all you should see on the outside of the gun is the very tip of the screw, in a pretty safe location.

8. Plug that bad boy in, fire up your favorite shooter, and destroy your old high scores!

Trying the Mod on a PS1 Namco Guncon

After a bit of tinkering around, I have found that it is just as easy and equally effective on Playstation 1 Namco Guncon guns.

Doing the mod on one of these Guncon guns is almost exactly the same, its just a little harder to mount the switch securely. the only real difference here is instead of soldering wire to the old switch, it (the old switch) has its own board which can be removed. the wires that go to this board can be snipped, stripped, and soldered directly to the new microswitch using the NO and COM posts.

Have Questions?

I hope you found this guide interesting and/or helpful.  If you happen to need more clarification I invite you to post your question in the forum thread so skate323k137 or someone else may be able to address them.