FX impact adjustments

[ashes5]

i bought the 30 cal. I have only shot about 500 rnds. 300 rnds were with a bad scope. Groups and shots were all over the place. Now I have a stable scope the groups are getting better. I am wondering if anyone has been playing with the different adjustments and seen good results? I am seeing a better group with the heavier JSB's. I haven't touched the adjustments from factory. Shooting at full power.
Has anyone seen improvements by changing any of the adjustments?
thanks for any feedback

MOD EDIT: moved to PCP section

 

[Txboy]

I have found with my impact 30 the best groups I get are with the 50 grain jsb. My groups were all over the place also. I was shooting about 860 fps. I adjusted my valve down until I found the sweet spot. 828 to 830 were the best results I got. At 50 yards I am shooting 1/4 inch 10 shot groups. At 100 about a 1/2 inch. Let me know if this works for you. My hammer spring is set to max

 

[Txboy]

Forgot to mention. I found that my groups tighten up if you really hold on to the rifle because the rifle does have some recoil. I suspect that unlike a powder burner where the bullet is long gone before the recoil, with a pellet gun the velocity is much slower the bullet is in the barrel longer. This is just a guess and I have no research to back this up lol. I just found that my groups improve when I really hold on to the rifle. 

 

[ashes5]

I have to beg my buddy to borrow his chrony. That's the problem with spending all your money on the gun. What bar do you think your at? Are you adjusting the secondary pressure in the back. Sorry for the newbie questions. I am really new to air guns but got hooked starting with the Marauder. Now I have to sell some of my shotguns to support my new habit.
thanks for the reply

 

[Txboy]

My pressure is the set factory pressure so I'm assuming 140bar being the gauge is not that accurate. I adjusted the valve which is located under the barrel above the bottle. This seems to be a really good fine adjustment. The hammer spring located on the back left of the gun is set to max. That is a more course adjustment. I think with the 30 the hammer spring has to be at max to get over 800 fps. At least that how my gun reacts to any changes made there.