The FX Verminator has a 3 step power adjustment on the left side of the barrel. remember the heaver the pellet the slower it will fly but the straighter it will fly and it will have more knock down power over lighter pellets
It depends on the model. Some have a dial to adjust the power like the Airforce Condor or the Shinsuin, other like the Marauder do not have simple adjustment dial but can be adjusted with a tool....
Their are several ways to increase the power of and Air Rifle. But you will need the right tools. Polishing the air chamber will help. Remove any burrs in the slide action will help. using lighter...
See the link below for "UK airgun law"It looks to me like under 12ft pounds is the limit. I've been told it 495 FPS (feet per second) is the max. Anything over that requires a special license.
Search the web. There are shops all over the place that modify air guns. (air gun repair). They modify the trigger and several of the internal PCP parts for more accuracy. A simple solution is to...