[This is my KJW m700 (original verision). I picked it up cheap for $100 and am currently adding mods/upgrades to it.]
The main reasons to take down your m700 is to swap out your hop up bucking or your inner barrel, or for general cleaning of your gun.
The tools you will need for this are:
- A set of hex keys (2 sizes. Metric keys fit perfectly but I don't know the metric sizes; otherwise use a 7/64 and a 1/16)
- A small Philips screwdriver (optional)
2) Remove the front bipod mount screw. Put a hex key or a small screwdriver through the hole and unscrew it. You only need to take the front one off, not the back one.
3) Remove the trigger guard. Use the 7/64 hex key for the 2 screws that hold the guard in place. The big screw goes in the back next to the trigger, the little screw goes in front.
4) Pull everything out of the stock. It will come right out after you remove the previous screws.
5) **Optional** Disconnect the hop up from the rail. You do NOT need to undo the 2 Philips screws on top of the rail. Doing this is only necessary if you want to get to your hop up adjuster knob. There are 2 small parts that make the adjuster knob work and they can get lost really easily -- so unless you are trying to get to them, I recommend leaving the rail the way it is.
6) Unscrew the outer barrel by putting a hex hey in a hole and rotating the ring to the left. Repeat until it is loose. Once loose, leave the hex key in a hole and unscrew it by hand. Then slide it off of the inner barrel. Be careful not to bend the inner barrel!
7) Remove the pin from the hop up housing. You can see it on both sides of the housing; it pushes through fairly easily. This will allow you to pull the hop up housing out of the rest of the assembly. After you remove the pin, you will feel the barrel and hop up housing hanging on the ring. Use a twisting motion while you pull and it should slide out with minimal effort.
8) Now you're down to just your inner barrel and your hop up housing. Here is the tricky part: there are 3 small hex screws that hold all that together -- 1 on the top holding the metal housing and 2 on the sides holding the barrel. You must remove ALL 3 to take it apart. Many people will tell you to remove the 2 on the sides and pull the inner barrel out, but doing this may ruin your hop up bucking. Loosen all 3 hex screws with the smaller key (1/16 standard size, I'm not sure what size for metric). They are small and easy to lose, so be careful! I recommend just loosening them instead of taking them completely out. If you're having a hard time turning them, here's a trick: put your hex key dead center on the screws. You only need a slight pressure and make sure you push straight down. Push and twist at the same time. It takes some practice, but this is what it takes to get those bastards out.
9) Once all 3 screws are loose, don't pull the barrel out. Pull the black plastic housing over the barrel instead, it should slide off.
10) See that red strip on the side of the metal housing? That's part of the bucking. Push that in with a hex key and pull the metal housing away from the bucking. You will want to hold the bucking as I'm doing to keep it on the barrel. Only once the housing is off of the bucking should you try to take it off. This is because there is a gap in the barrel where the hop up adjustment goes through, and if you yank it over the hole the bucking can rip.
Here is an example of what it looks like inside the barrel. See the V shaped nub on the top? That's only one of the potential parts that can be ripped if you yank the barrel out. By the way, most buckings don't have that V inside of it, I got an Angel Custom bucking from Evike.com which has the V built in. It works very well!
11) Now you can replace the hop up bucking or you can clean any residue off of it. It's important to clean the bucking to make good contact with the bb's. A Q-tip is perfect for this, but try not to leave any Q-tip fuzz inside your barrel. You can also disassemble the hop up chamber if you want to replace the hop up nub inside of it. Some make their own custom shaped nubs from hard plastic such as PVC (I didn't need to since I have the V built into my bucking).
And that's all there is to it!
What do you guys think? Is there anything that I missed? Please leave comments/feedback/questions below, I'd love to hear what you guys have to say!
And that's all there is to it!
What do you guys think? Is there anything that I missed? Please leave comments/feedback/questions below, I'd love to hear what you guys have to say!
