FX FX M4 800mm

Hi,

Im new in this forum and I’ve heard positive things about the community so I give it a shot, pun intended. I just bought the gun and Ive been studying a lot from videos and forums, BUT still having open questions.
1. Is the 800mm rifling 1/16?
2. Anybody willing to help me getting quick setup for JSB Exact King .25 (25,39 grain) pellets?

Was thinking just to go basic setup with 4 lines, 3 and 8. Those circled values. Am I on right track?
My plan is just to zero the gun for 30 or 50 meters and to have decent grouping. Going to tune it later after I get radar to measure speeds. Going to range in 5h and have no time for more research so asking for community.

Thank a lot!
 
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it isnt rocket science, Take your time and enjoy the process:)
Seriously not rocket science, but Im kinda guy who wants to understand why, instead of learning by trying. (learning by trying is ok if you are 100% sure its not going to break anything).

So my understanding and logic tells me this.. Keep plenum pressure 150 (im tuning for heavy slugs)

1. You open front valve open so hammer can work with plenum 'freely' while adjusting it
2. You reach optimal velocity by increasing or decreasing the hammer wheel. You can fine adjust it by long flat thumb roller
3. You start closing front valve so you dont waste air after shot is made, when closing it and seeing drop in velocity, turn it bit open

There it is. Or atleast that how my brain works it out.