T A-5 wrote: im thinking of buying a low pressure kit to go along with my palmers stab.....i use c02 and i want to know if the opperating psi is differnt from when useing nitro if so what is the best psi for running c02.

You are going to run the pressure at which your marker operates. It is a trial and error process. You will find that your pressure is lower than it was but you are limited on how low you can go due to the pressure required to cock the hammer.

The following process has worked well for many. You turn your velocity screw out to the point it is nearly flush to the inside of the power tube. Then turn the pressure up on the regulator to obtain about 325 fps velocity. Then turn the velocity back in to bring velocity down to about 275 fps. From then on you use regulator adjustments to get the velocity you need.

If the marker is not cycling  (cocking) properly, then run the velocity in more (reducing the velocity) and again raise the regulator pressure to get the velocity back. If you install a gauge on the low pressure side of the regulator you will likely find that you cannot drop below 300 psi (if you can go even that low) and maintain reliable cycle of the marker.

The object here is to slightly restrict the power tube passage way to increase the blow-back pressure to cock the bolt. Once you understand how the marker works adjustments become intuitive.