FX Wildcat MK3/Maverick tuning question

What does it mean if I am shooting at 930 fps on Hammer setting 7 and then it jumps up to 951 fps when I turn it to hammer setting 6? I thought it meant that I had too much hammer on setting 7, so I turned the hammer adjustment screw clockwise but it still shoots at 930. I thought by turning it clockwise it would be the same as turning it down to setting 6? No matter how I adjust it in or out it doesn't hit the velocity that it does on hammer setting 6. Reg settings 150/110 with 13.14gr hammer, shooting 23gr slugs using slug port, any ideas?
 
The internal adjuster is for making very small adjustments. Try turning it all the way I. And see if there’s a difference. If not. Back down to 6, and start turning the internal adjuster out again till you see power start to drop off. Turn it in till you see a 5fps difference, and you’re basically tuned before the knee where you want it for that reg pressure. If it’s not your desired speed, time to up that reg pressure.
 
What madeintheuk said and you don't need the slug port for that light slug, and you may have too much hammer weight. Your regs are fine. I'm assuming a .22, in my limited experience, you won't have the fine control with the slug port as you would with the pellet port. Your SD may wind up being greater then you'll start chasing that. Try starting with your HSA at 19mm over all length and see what happens. My Mav .22 started out as a .25 sniper and I've never changed the hammer, guess I should someday. but it works fine for me.
 
Exactly what Uk said. Turn that screw in. Eventually the speed will go down. Then work your way back up to that max point. My Maverick is quite picky. When you do find that sweet (small) spot of harmony between hammer and reg pressure it performs lights out sending every shot almost the same speed. Wander off that spot much and ES goes to hell fast. I am admittedly too anal about ES as accuracy is what really matters but I find the power wheel utterly useless. ES jumps to 20-30 quickly. My compact stays maxed for the ammo I shoot.