Nah, if you have even the most basic tools this is a cinch. I realize that you want to be safe with something that cost you lots of money, but relax and have faith in yourself. Besides, it'll leave more money for paint
BTW, don't worry about getting a particular numeric pressure setting. Every marker is slightly different so every marker will work best at a different pressure. In addition, I suspect the accuracy of most gauges anyways. +/- 10 PSI is definately within the error of all of the gauges I've used.
OK, here's the deal with any type of marker that uses a sprung hammer and a stem type valve. If you increase the pressure to the marker you will shoot hotter. No kidding Einstein, right? However, if you continue to increase the pressure past a certain point, the velocity will begin to decrease due to the extra effort needed to open the valve. The hammer spring can only hit the valve stem so hard.
Assuming that the more delicate bits internal to your cocker could take the pressure (don't try it, since they can't) you could theoretically increase the input pressure to the point that the valve couldn't open at all.
So, in short, the paint velocity would be zero when the input pressure was zero AND when the input pressure was really high.
That means, assuming that you want to shoot below the marker's maximum velocity (you do), there are two input pressures that will get you there - one below the max and one above the max. You probably want the lower of the two since it's easier on paint and I've never seen a shootdown problem due to the stock reg's setting. Especially if you have a new-ish cocker.
Now that the classroom portion of our lecture is done
, here's what you want to...
I assume that you have a standard cocker with the stock WGP reg. This will require a bit more work than something that you can adjust externally, but the process is the same. In addition, if you have a different reg, I can't tell you which direction is down and which is up. I know that the AA Vigilante is the opposite (OUT is DOWN), but besides that, I can't tell you.
1) You need to turn the output pressure of the in-line regulator DOWN. First, get the gas-fitting endcap off. The body of the reg is 3 pieces. The endcap that screws into the marker is one, the main body is another and the endcap that you screw the gas input into is another. To get these apart without scratching the finish, I put ~10 or more layers of duct tape around each piece then go to it with a pair of adjustable gap pliers.
2) There is a large screw head that will be under the cap. It is almost the entire diameter of the regulator. If you don't see a slot that a large flat-head screwdriver would fit, you unscrewed the wrong end. Once you find the screw, turn it IN about half a turn. This will decrease the output pressure.
3) Put the endcap (with the gas fitting attached) back on. Just finger tighten. There's an o-ring that will seal it. Gas it up.
4) Check to see if the marker cycles properly. If so, repeat steps 1-3 and lower the pressure some more. At some point, the marker will not cycle correctly and it'll do all kinds of bad things. DON'T WORRY, it's not broken. When it reaches this point you know that you've gone too far, so turn up the pressure (turn the screw OUT about a half turn).
5) Notice that all of this you can do in the comfort of your own house in front of the TV. However, this last part you need a chrono. Now you need to adjust the speed between the input pressure and the hammer spring strength. Most likely you will need to increase the pressure slightly in order to shoot just under 300. Of course, try to achieve the fine tuning with the standard velocity adjustment on the hammer.
Ok, I realize that this seems like a lot of work, but I encourage you to try it. There is very little that you can do to mess this up, so it's a good introduction into basic cocker maintainance. If you need help e-mail me at email@example.com
. I'm always willing to help 'ballers take good care of their gear.