(PLEASE read this before continuing or asking any questions)
1. You should never use CO2 with plastics. The low temperatures of the gas output from a CO2 canister reaches levels that are outside of the operating range of most plastics. Prolonged exposure to such low temperatures will lead to increase brittleness in plastics, and eventually your gun internals will fail irreparably. This guide is written ONLY for using High Pressure Air paintball tanks. 2. Do not attempt to fill any tank or pipe beyond its maximum pressure rating. Doing so could lead to serious bodily harm since ruptures also involve shrapnel. 3. Do not attempt to cycle any Nerf gun at pressure levels above 40psi unless it is known that they can survive higher pressure levels. You will have pressure gauges handy to test the maximum operational pressure level of the guns you intend to use with this setup and can then set the regulator(s) to output air to the gun at that level. 4. I DO NOT recommend hooking up a regulated output to the bladder system of a Nerf gun such as the Rapidfire 20, Powerclip, or Magstrike. The output from a high pressure air tank is very fast compared to the manual pump and could introduce significant wear and tear on any kind of flexible tank. It will be safest to replace the bladder tank with a higher volume rigid tank.
It took a good deal of time to find the RIGHT parts to use for this. The first HPA paintball tank I had was the cheapest of the cheap and had a miserable flow rate. The second one I got used an adjustable on-tank regulator. That setup works great, but doesn't allow you to switch tanks.
Paintball regulators (particularly this model) do not offer very fine adjustments so I decided to double regulate the output. This is done for safety and simplicity.
The operational steps to use the setup with a single-fire or semi-auto are
2. Press push-button valve to refill weapon
The operational steps to use the setup with an automatic are
1. 3000psi HPA paintball tank
I am using a Pure Energy 3000psi 48 cubic inch aluminum paintball tank. Any HPA tank could be used provided it includes a fixed regulator. 4500psi tanks will cost much more. I simply went for the most affordable high volume 3000psi HPA tank I could find.
Price = $65-$85
2. ASA adapter
Used to adapt the ASA fitting of the tank to 1/8 NPT. This part can be solid-mounted to your blaster if desired.
Price = $5.50 from e-paintball.com
3. Stainless Steel High Pressure Hose
Alternatively a 1/8 NPT pipe nipple could be used if you choose two of the same ASA adapters that will not interfere with the installation of the tank. This part simply bridges between the ASA adapter and the inline regulator input port.
Price = $11.52 from e-paintball.com
4. AIM inline regulator (low pressure version)
Set this to 0-70 psi for a magstrike, or 35psi for single-shot blasters
It's output is adjusted using an allen wrench (clockwise for increase, counterclockwise for decrease). Just be very careful when setting its output level. Just be very careful when setting its output level. In order to avoid destroying your Nerf blaster prematurely it would be a good idea to hook the regulator up to a ball valve in order to get the output pressure set correctly beforehand.
Price = $45 from e-paintball.com
5. ASA adapter
Used to adapt the ASA fitting of the regulator to 1/8 NPT.
Price = $5.50 from e-paintball.com
6. Output gauge (0-160psi)
You will need two instant tube fittings, a pipe tee, and a gauge if you want this inline with the tubing. This will monitor the pressure level supplied to your blaster. Alternatively you could simply replace the gauge on the inline regulator.
Price = $4.88 (mcmaster part# 4912K71)
7. Output to gun
The last length of tube running to the fitting linked to the internals of the gun. I would advice using these parts to adapt from hard tubing to the soft tubing inside the blaster. Mcmaster part# 51025K243 & 5047K15
Optional: Push-Button or Toggle Valve
This valve is routed to an easy to reach location either near the gun or on your chest so that you can disconnect the gun from the tank, or use it as a refill button for single-shot blasters.
Price = $14.75 (mcmaster part# 6790T42) for push-button or $4-16 for any toggle or ball valve
Hookup to air system of the gun.
For more details on this see my other write-up: DIY: External Air Tank or ask me through PM about advice concerning how best to hook up to the air tank of specific guns. Most Nerf guns use 4mm ID tubing which you can by Tees and threaded adapters for through McMaster. Simply search for "Metric Barbed Tube Fittings".
Most blasters include compression nut fittings which can easily be disconnected, allowing you to replace the stock tubing with more durable tubing of identical dimensions.
For tubing I would highly recommend 1/4" OD Extra-flex Nylon tubing. It has a maximum pressure level of 180psi, a bend radius of 3/4" (so it's fairly flexible), and it's compatible with instant tube fittings which make it easy to maintain and reconfigure the tank system. You'll need 10 feet for the tank setup and it's easy to cut to length with a box cutter or scissors.
Price = $0.67 per foot (mcmaster part# 9685T3)
Instant Tube Fittings
You will need 1/8" NPT to 1/4" tube OD fittings for most things ($12.60 for 10 mcmaster part# 9087K11) as well as a straight coupler (part# 9087K61). Whatever other fittings you need will depend on which gun you are hooking up to.
And that's the revised basics. Per tank fill, which costs only $4 at my local paintball shop, this setup gives me 200-300 shots using the Titan and 1200-2000 shots using the Magstrike. It's already proven very effective in the preliminary stages and I hope to use it much more in the future. The Low Pressure tank I'm using now has 141 cubic inches of volume which at 90psi is enough to fire 90 shots from the magstrike or 12 from the Titan. Then the Low Pressure tank simply gets refilled by the High Pressure tank.
Amended with new configuration on 09-07-08
Edited by CaptainSlug, 07 September 2008 - 02:04 PM.