Fubarius'Detailed Modifications

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Come on people, I know you're tricking those Marauders out! Send me those mods!


Ok, fair warning, this message is going to be a long one. If I were you I'd hit the bathroom, grab a Mountain Dew Code Red (official soft drink of my long ### posts), and maybe a sandwhich before continueing.

All situated? Good. Let the tech-novel begin.

Now before you go and start buying things, you have to understand a few really simple concepts. First, you'll never find a "Marauder Expansion chamber kit". Face it, it's a cheap entry level gun and wasn't designed with the intention of it being modified later. Does this mean don't modify it and just sell it? Heck no! Modifying cheap guns can be extremely fun and rewarding, and is a great learning experiance in case you ever upgrade to a more expensive gun. Best to get all of the "oops, shouldn't have done that" mistakes out of the way on a gun you can afford to replace if neccesary. Plus it shows you have more grey matter than those who have to have the local airsmith change an o-ring for them and who think the best "upgrade" for a Impulse is moving the regulator from the bottom line to a vertical position. (hint, it doesn't change performance one bit, just moves a reg). Second concept is pretty obvious, but not everyone seems to get it right away. For something to screw into something else, they must have identical threading patterns. You can't thread a 1/8NPT hose(stands for National Pipe Tapered thread for 1/8 inch internal diameter pipe, which actually is 3/8" in outer diameter and has 27 threads per inch) into a 5/16-24 hole (5/16" outer diameter with 24 threads per inch). That first thread is the standard threading of hoses for paintball gun accessories, and that second is the threading for the Marauder bottom line. As you can see this is going to require a few special tools to make work, but it's not as hard as it sounds.

Now that you hopefully understand those two concepts we'll go step by step. I'll list off parts needed as I go (they'll be in all capitol letters) so I can explain what they do and why you need them. It's actually easier than just spewing out a parts list, trust me. Just make sure to read the ENTIRE instructions before you do anything.

First, we need to get that stock hose off. To do that we need to get the grip frame off. Pull out the pull pin on the grip frame. Now using a small pin punch (or small nail, allen wrench, etc.) and a hammer gently tap out the small pin that's on the very front of the grip frame. Don't loose it, you'll need it later.

Once that pin is out you can completely remove the grip from the body of the gun.

Now unscrew the hose from the grip frame, it unscrews counter-clockwise (for those of you who've never actually seen a clock with hands, that's turning it to the left). It will probably come out by hand, but you may need a wrench.

Now remove the hose from the body of the gun. It's in there pretty tight and it unscrews clockwise (yes, the opposite way of the hose, and just about anything that unscrews). You'll need a wrench and it's very important that you don't try to turn it counter-clockwise. You'll just get frustrated as it gets tighter instead of looser.

Once the hose is off, we can get an EXPANSION CHAMBER. Expansion chambers have the exact same threading on them as your CO2 tank. So compare your tank threads to the hose threads and you'll see that they are very differant. The tank threads are known as 1/2NPS (National Pipe Straight for 1/2" inner diameter pipe, actual size 7/8" with 14 threads per inch). The hole in the body is 1/2-20 left hand (1/2 inch outer diamter with 20 threads per inch, and is threaded backwards so turning left goes in instead of out). Now to get that expansion chamber to attach to the gun you're going to need an adaptor. Since an adaptor like that would allow you to actually screw your tank vertically into your gun it's known as a VERTICAL TANK ADAPTOR (this was a popular way to have the CO2 tank positioned years ago). Now don't go looking for a Marauder vertical adaptor, you won't find one. However a couple vertical adaptors are compatable. Here's a picture of two.

On the right is the easier to use, but a bit more expensive, Avenger vertical adaptor from http://www.Dropzonepaintball.com .It's $25.95 plus shipping. It does work very well and is considerably lighter than the other one.

That other one is the stock vertical adaptor from a Raptor. It can be found at http://www.paintball-adventures.com .

Scroll down a bit, you'll see it. It's considerably cheaper at $12, but heavier and you may have to fill in a tiny vent hole at the base of the threads (if you buy one, you'll know what I mean). A bit of JB weld, a metal epoxy found at any hardware store, will do the trick.

Now take your vertical adaptor and screw it into the body of the gun. The dropzone one will seal with the included o-ring, the raptor one will need some TEFLON TAPE (also found at the hardware store. Get some, you'll need it in a couple of steps).

Remember the vertical adaptor screws in counter-clockwise.

Now screw the expansion chamber into the vertical adaptor. Don't over tighten, you'll start to loosen the vertical adaptor. With some expansion chambers the out side can be rotated around the middle (my Lapco one, ACI chambers, a few others), usually be loosening a screw and twisting the out side of the chamber. Use this to possition the hole for the hose into the chamber to where you want it. If you're right handed I suggest either to the right side or in the back. Now for hoses. The stock one won't screw into the expansion chamber. So get either some STAINLESS STEEL BRAIDED HOSE (though it's tough to know how much length to get), or the easier to install MACROLINE. Macroline is nice since you just screw the fittings in, cut the hose to length, and push the hose into the fittings. If you want to go with Stainless hose I suggest getting everything else done first and then taking the whole thing to a paintball shop to hold up different lengths of hose to see which fits best.

Now we come to the tricky part. The hose that screws into the stock bottom line (dohicky the tank screws into), and the hose that screws into the expansion chamber are very different. There are two ways to fix this. One is to cut new threads into the stock bottom line with a tool called a THREAD TAP

You can get one at your local Hardware store or Sears. Look for one labled 1/8NPT, though at sears they call it a 1/8-27 Pipe tap (same thing). Follow the instructions that come with the thread tap. You'll have to drill out the stock hole a bit, using the size hole indicated by the tap's instructions. Then slowly force the tap into the hole so it cuts new threads as it's screwed in. It's a good idea to practice on some scrap material to get the feel for it.

If you screw that up, or don't feel like spending $5 on a tap, you can try literally hacksawing off the stock bottom line and then drilling some holes in the bottom of the grip to mount a standard aftermarket bottom line.

I suggest removeing the left grip pannel from the grip frame so you can see how much material you're removing so you can make sure you leave enough to support the weight of the tank. Someone posted pictures of a Marauder with this setup a while back, I'll have to try and dig it up later (no time tonight).

So, did that cover everything? Feel free to e-mail me at fubarius@hotmail.com if you have any further questions.

Dave Johnson
aka Fubarius
Four out of five voices in my head think I'm completely normal.


Ok, so you want to add a drop forward to your Marauder (or Eradicator). First, you'll want to read the instructions for adding an Expansion chamber.

If you don't want an expansion chamber, just use a hose adaptor and a standard paintball hose instead of the expansion chamber. But trust me, the stock hose won't work.

Now we'll move on to adding a drop forward, which was briefly covered in the first article.

The ASA adaptor (dohicky the tank screw into) is molded directly into the grip. We'll want to get that metal part out before we do anything else.

A cut lengthways along the ASA (a dremel works great here)...

And one accross the other side, then some prying with a screw driver will pop it out...

Notice the narrow part on the metal insert. The plastic is thicker where it fits into that groove, so it may take a bit of force to get it to snap.

Next you'll want to remove the grip cover on the left side of the gun before we do anymore cutting. We want to make sure there's enough material left to support the weight of the drop forward and tank.

You'll also notice how much paint builds up under that thing after a hard days play

Now to shape that mess into something a bit more attractive. Start on the front of the grip. A quick cut with a hacksaw or dremel...

You'll also notice how much paint builds up under that thing after a hard days play

Then some more fine shaping with a file, sandpaper, or dremel to make the front of the grip nice and smooth.

For the bottom, you want to leave as much material as you can and still have a level bottom. Or you can have it angled down a bit if you want. I prefer level myself.

Now sawing through the bottom by hand and keeping the cut straight and level can be tricky. A miter saw makes it a heck of a lot easier and quicker.

You'll notice on mine there's a few notches left on the very bottom from the metal insert...

You could try and cut a bit more off the bottom, but I left them since I wanted as much material on the bottom as possible, and they get hidden by the drop forward.

Now to mount the drop forward (or regular bottom line if you that's all you want). First line it up on the gun where you want it and mark where the holes need to go. You want to make sure you're not screwing into where the grip panel screw is. The grip is quite a bit longer than a normal 45 grip on the bottom, so you can squeeze both screws behind the grip panel screw hole. For screws I used a pair of 1" drywall screws. Cheap, easy to find, thread right into the plastic, but I suggest pre-drilling the holes a bit.

Other options include drilling through the grip and using nuts on the inside. Or using a threaded insert in the plastic.

Then all that's left is to replace the grip panel, add your expansion chamber, and add the hose.

So here's mine totally complete with a modified Raptor vertical adaptor (recently replaced with a Lapco Avenger vert, a review on that later), Lapco expansion chamber, Lapco drop stock, and a Lapco Bigshot barrel.

Dave Johnson
aka Fubarius
Four out of five voices in my head think I'm completely normal.

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