Introduction: Nerf Gun Modification 101
I bought a Nerf gun. Ya, that's right. It happens to be the CS-6 Longshot. Seeing as how it's a sniper rifle, I figured it could stand to shoot like one, too. So far all it does is shoot a little foam dart about 30-40 feet max, and I really want it to go more like, 100 feet. It sure would be nice if I could leave welts on my friends, too. So, check it out, all you need is a little time, patience, spring, o-ring, and sealer-stuff.
Step 1: Disassembly
Basically, the gun's held together with A THOUSAND screws. They're sort of small, phillips head screws. Some are longer than others, mainly the front 2, so try to keep track of where they go. If you need help, try what I did by laying them out in the shape of the gun. The only hard part about taking it apart is that dang bolt. It's the big orange thing you use to cock it. You can remove it by carefully prying it with a wide, flat-bladed screwdriver. As is true with what seems like all Nerf guns, they're just screwed together.
Step 2: Upgrading: Part 1
Now it's time to make this thing work well. There are 3 ways that really help performance.
The first is to upgrade that big fat spring. It's found in the big orange cylinder. Right now it's about 2 inches in diameter and around 6 inches long. You have 3 choices. You can add a second spring, you can stretch it, or you can use a spring from an AR-15 assault rifle.
If you decide to stretch the spring, make sure you know what you're doing. Spring manufacturers know what they're doing. When you grab it and stretch it, it will work well for a few times before it gets worse than how it used to be. My bet would be that if you have to do this, you can stretch it, hit it with a blowtorch, and let it air-cool.
A second spring doesn't seem to help, unless it fits perfectly. The best thing to do is get one from the AR-15. They're about $15, and the same size except 11 inches long. You'll want to cut it down, but man will that thing help.
Step 3: Upgrading: Part 2
The second thing is to upgrade the seal in the cylinder.
The gun comes with a tiny, almost worthless o-ring. You'll see it once you pop open that orange cylinder. Basically, the gun works by giving the spring potential energy. Then you move the bolt forward and create a large cavity of air in front of it. When you hit the trigger, the spring is released, compressing the air and forcing it out of the cylinder. It ends up going inside the dart, and this compressed air moves the dart at your target.
There are 2 ways to upgrade the seal. The first is the easiest. Get a fat o-ring that fits well. When you do this, you'll want to get one that's smaller than what you'd think would work well. Getting one that's too fat will cause the weapon to malfunction, and you won't be able to move the bolt because the o-ring exerts too much force on the walls of the cylinder.
The second way is to get a couple metal washers and a nylon washer. This is nice because it gives you a seal that's not overkill, and a little stronger than before. Unfortunately, the rest of the gun is still plastic, and in some cases weak.
Step 4: Upgrading: Last Part
Last thing to do is to plug up the hole on the bottom of the beginning of the barrel. You'll want to be very careful when you do this. It's right after the orange cylinder, and keeps the pressure inside the dart from getting "out of control." What this thing does it take all your compressed air that your spring just made, and throw half in the trash. Sealing this hole will allow you to throw more air in the dart, applying more force and shooting it faster and farther. This is what will really help you welt your friends.
Do this by using some sort of really good epoxy or silicone gasket maker. First make sure the whole and surrounding surface is clean. Then very carefully, kind of work it in the hole but not through it. If you use too much, it will stop the round from moving. If you use too much on the outside, it won't go back in the cylinder when you pull the bolt back.
Step 5: Put It Back Together and Test
Now comes the fun part. When you're ready to put it all back together, make sure everything lines up to begin with. There's a part of the cylinder that needs to fall in to the right side of the gun. There are also 4 orange rollers on the bottom of the cylinder, 2 on each side. They need to fit into a guide in the gun half. Double check everything, and find out if it works best for you with it cocked or not. The part that I had trouble with was the thing that catches the spring holder. That kept popping off, but it eventually went back together. Once you get it screwed together, you can start launching darts at crazy speeds, and even sell these bad boys. Maybe you'll make some money!