Tube Bulking
The other half of what I promised a year or so back. It's better now than it would have been then. ;^) So must have been worth the wait. If you find mistakes let me know.
Before you start. Decide how much you wish to spend on the project, how you want it to look and find out what parts are available for you to use. Some links to help you on your way.
There are many tanks to choose from
Tank bulk offers a way to bulk and have hundreds of shots between fills. The number of shots you will get depend on the tank you use as well as the tune of your gun. Here are some pics of different tank bulk options that I have done.
Part one
ALL FAKE CO2 BULKING ADAPTERS THAT USE WITH 1/8NPT PIPE FITTINGS
Choose the adapters once again there are many to do the same job. One of these offered by several of the companies we have already visited is the fake co2. This usually aluminum adapter fits in your gun where the co2 cart goes and often looks like one. In the center I have included the 1/8 npt to asa adapter that screws into the fake co2 so you can hang a tank from your gun. These two are the only required parts to hang a tank under your gun. On the left is one type of on and off valve that can be used on your tank in case it does not have one.
The fake co2 adapter seals against the front of your stock valve and has a threaded 1/8 NPT hole in the side. Your tube cap is screwed into place and holds the adapter just the same as it holds a co2 powerlet.
1- A large hole, circled above, usually ½ inch, is drilled in the side or bottom of the main tube of your gun in a place that corresponds to the threaded hole in the fake co2. You can measure or guesstimate center punch and drill a pilot hole. Then the large hole. If you are off a bit you can file or use a dremmel as needed.
2- The burrs caused by drilling will need to be removed from the inside tube a fine toothed round file works well. Unless they are removed it could be very difficult to get the gun back together.
3- Hoses can be run to a remote tank or a 1/8 to ASA paintball adapter that can be screwed directly into the fake co2 so the tank of your choice can be hung from under the gun Use the blue lock tight on all of the fittings when you do the final assembly to prevent leaks and keep things together. Macroline and fittings available at your friendly paintball shop were used here. They are extremely easy to install as once you have the fittings in place you simply cut the line to size and push the ends into the fittings. To tight of a bend can cause leaks.
Part two
DROP-FORWARD INSTALLATION
1- To install the tank under the grip a paintball drop forward can be used. First the bottom of the grip frame must be flat. The metal is soft not much needs to be removed so a file will do the job quickly.
2- Holes need to be drilled that correspond to the hardware you are using. Mark the holes, center punch, pilot drill, drill and then tap for the size and thread of fastener you are using. In this case number 10/24 screws were used. There is a thick piece in the bottom of the frame at the front, see the picture above, that can be drilled for better strength as most of the metal on the bottom is fairly thin.
Part Three
IN THE STOCK BULK
1- To put the tank in the stock you will need to drill some large holes through the stock. If you drill them the right size and in the right places the tank can be snapped in and out for filling. The placement and size of the holes will depend on your tank and valve as well as other plumbing you choose to use. Braided stainless line was used here. It is like house plumbing you must put one piece together at a time sometimes installing the line to the parts then installing the parts on your gun. They are bulletproof though and once installed you can forget about ever having leaks.
2- Use a Unibit to make the holes on the inside of the stock to hold the tank and on/off valve. After drilling a pilot hole in the correct spot turn the Unibit with Channelocks or a 90degree drill if you have one. Remove the material from the inside to enlarge it to the desired size. This makes the holes on the outside of the stock smaller and leaves more material for strength.
3- There is a hollow spot in the stock just behind the grip. This makes it a good spot to drill and install the braided supply hose.
4- The front connects to the fake co2 as in previous sections. A hole is drilled through the grip as well as the tube a 1/8 NPT male female adapter or pipe and fittings can be used to extend the line through the grip. A 45 degree male female NPT fitting is used to angle the hose under the stock
T-Copper came out with a nice bulk unit that will allow one to turn a tank into the stock for the gun. The unit comes with a screw in fake co2 adapter, and a steel line that screws into a fitting that becomes the rear plug of the gun. No permanent mods need to be done to install this unit as T-copper offers it. Early in my modding days before I knew about valve volume I simply made all the holes and tubes feeding the valve large installed a lighter valve spring and had gobbs of power. That is why you see the larger line screwed into the side of the red gun. I have since learned that one can get many more shots at or above the power level previously achieved by using the correct volume in the valve as well as springs porting ect. One can get plenty of shots from an eight or nine ounce tank. So this is a great tank bulking mod.
The advantage over tube bulking are many more shots. And many tank options. Yes once again for cold weather shooting you can use an HPA tank of air or nitrogen. Larger regulated paintball tanks can be used here too and can give you plenty of shots in the cold with pressure to a max of 1500psi at your discretion. Disadvantages are the bulk, weight and to some appearance as well as a permanent hole in the tube for some of the mods . A good portion of the paintball drop forwards and other gas accessories can be utilized on your airgun. As you can see there are many ways to do this limited only by your imagination and pocketbook..