I'd do it your self, there is a break down drawing on Fx's web site. Look at the Royal's there the same gun. The bobcat just has a linkage for the trigger. It has all the O-ring sizes and hardness that you'll need. You can go hydra PAC and get the o-ring. When your putting it together use a small amount of silicone grease on the o-rings for lube as you assemble it. It sounds like it may be the power adjuster o-ring or the breach o-ring. Both are very easy to change. The worst part is taking your scope off, forcing you to re zero. There's a small detent ball when you remove the power adjuster to be carful no to loose. I like to remove the barrel when changing the breach o-ring. It make it very easy to install the new o-ring. Now some will argue what's easier. Fill free to pm if you have any questions