How hard is it to tune this gun? Can I get away with just installing a stiffer hammer spring or do I need to adjust the regulator? I have taken apart almost everything on this gun except the regulator. I've read you shouldn't mess with the regulator if you don't have the proper tools and I don't have the proper tools (the tool that checks what the regulator is set at). A few months ago, I experimented with different cast bullets made by Mr Hollowpoint and the best bullet my gun shot was the 119 grain hollowpoint. The problem is this gun doesn't have the extra power to sling the extra 38 grains of lead as fast I want it go. The gun is shooting the jsb's at 761 fps and the hammer spring is a quarter turn to being max out. What I hope to do with my gun is to have two settings on my gun: one setting set for shooting 81 grain jsb pellets and another setting to shoot 119 grain hollowpoint bullets. Is this possible to do this on my own or should I just send in my gun to get it professional done. I think I'm mechanically incline and I can figure out how to work on most things but will I be over my head if I start this project? If you are asking why I want to do this, I just want to see if this gun is capable of shooting cast bullets and I would like to know how the jsb's will perform at higher speeds. As of right now, if I had to guess what the speed of the bullet is, it would be around 500 fps and I was hoping to get the gun to shoot the bullet at 760 fps and the jsb's at 900 fps. Is this possible or will I be jumping in to a pile of sh*!?