Tuning a Sniper II Gendel's Way

This is how I like to tune my Snipers (assuming you are going for low pressure).

1) Get a good low pressure gage

2) Get a good USED (this is important) regulator I like Stabilizers, ANS GenX-II, AKA Sidewinder or CP (non-CO2). I like used or well exercised 1000 cycles or more so I'm sure the spring pack has settled in for more consistency shot to shot. New regulators tend to flake out on consistency at bad times.

3) Have multiple, different spring rate, compression springs for both the main and valve springs. Tuning is trial and error and patience.

4) The lower pressure you want to go the heavier the hammer needs to be. Free Flow Tungsten hammers are great for real low pressures but hard to find. Shocktech also makes a stainless headed brass hammer that is heavy too. Though you can find old brass stock hammers and many different weight "stock" steel hammers to work with too. I pick up loose hammers all the time to have different weights available for different setups.

5) Find a port or add a port to attach you low pressure gage to the output of you regulator.

6) Find the center of your regulators adjustment and adjust your regulator to that point (no air required)

7) pull you main and valve springs and test your collection of springs and place a light weight spring with your valve and a medium weight spring for your main spring (reassemble) and adjust IVG to mid way.

8) Adjust your trigger pull/sear break to a comfortable position.

9) make sure everything is assembled ready to put air on the gun.

10) Cock your Sniper (this takes pressure off the valve so it will seat) then air up gun and set regulator to desired pressure (you will have to dry fire the gun a few times to get good consistent readings. When you air up the gun, even already cocked, you might be leaking air down the barrel/out of valve. This is a sign your pressure is too low or valve is damaged/dirty or the hammer is not cocked so dry fire a couple of times. If it seals you are fine if not you either have to raise you regulator pressure or put in a stiffer (heavier) valve spring.

11) If every thing is at the desired pressure and it is not leaking, dry fire the gun and see if the valve is leaking after being fired and the hammer is forward. If it is leaking at this point back out the IVG until it consistently does not leak with the hammer forward. If you have to back out the IVG most or all the way back, try going with a lighter main spring.

12) Now that you have the gun aired up and not leaking, at your acceptable pressure, you get to now chrono the gun. Hopefully your gun will chrono somewhere near a reasonable velocity but if it does not no worry just some more trial and error to get it there:

1. If the velocity is low screw in the IVG until it:

a) obtains the desired velocity with out leaking (you now are essentially
done).
b) If the IVG bottoms out or nearly bottoms out. This means you need
a heavier spring and start IVG adjustment again after it is replaced.
If the valves starts leaking with the hammer forward you will also
need to use a heavier valve spring now too (I said it is trial and
error, sometimes more error then trial )

2. If the velocity is high screw out the IVG until it:

a) obtains the desired velocity with out leaking (you are essentially
done).
b) The IVG is most or all the way out, this means you need a lighter
main spring and/or you need a heavier valve spring (but start with
the main spring for quickest results).


This is not as hard as it might sound just take your time have plenty of air on hand and do not get frustrated. You are balancing two springs, air pressure, hammer weight and main spring adjustment to get your gun to work consistently at your desired pressure. Rarely can you use someone else’s setup and get they same results they get since there is such great variance in springs, valves and volume behind the valve, which all play a part in how your gun functions. You do not have to replace your stock valve in a 2K+ Sniper it has sufficient flow rates and consistency to achieve low but not ultra low pressures. The other mentioned valves do work better but the gain is subjective mostly and the cost is more. That being said my main sniper uses and Rat valve and my backup uses a CCM valve.

I do not recommend you try to set your gun for sub 250 psi. You loose both a lot of efficiency and shot to shot consistency. I have actually raised my personal snipers to between 300-400 psi for better constancy and greater air efficiency under 300 psi you are trading efficiency for marginally quieter gun and below 250 psi few people I've know have great luck. I actually had my gun down to approx. 180 psi and it functioned fine but was a gas hog and the shot to shot consistency was off not as stable as it is now.