Reply To: FX Impact STX reg creep

Forums PCP Airguns FX Impact STX reg creep Reply To: FX Impact STX reg creep




You have to find the correct balance, this is very difficult if not done methodically/in the correct order. Firstly I feel that your reg is too low for .25 25gr, I would aim for about 128Bar. Then I think that you are over stroking the hammer, look for a distance of about 18mm, leave your valve open. Doing this will bring your gun closer to the default configuration for .25. Definitely have a look at the impact troubleshooting manual, the gun should perform at the default setting to a certain standard, if yours does not when set up at defaults then there may be some other issue that needs to be addressed, like a torn c3 oring, slow leak or leak during the shot cycle.

You need to have a velocity in mind before tuning, around 910 fps is a good starting point, you then need to adjust the hammer until you get to about 920fps. Then start with the valve adjuster, until you get to about 910 FPS. Doing this means that when your reg creeps you have enough hammer to overcome the extra pressure, then when the reg settles down the valve limiter stops the over speeding. If your gun is in tip-top shape you will get about 10fps ES if not then about 20 FPS ES.

If your gauges are the standard type then unfortunately you can't be sure what pressure your reg is actually at, and you are just going to frustrate yourself making adjustments. A low reg pressure and long hammer dwell is wasteful, rather try a slightly higher reg and shorter hammer dwell time, especially for .25

Get orings, leak detector, good tools, silicone grease, mosquito forceps and oring picks, there aren't many issues that cant be sorted if you have the right tools and the troubleshooting manual.