Fx maverick shooting all over the place will get 912, 889, 856, 816. Which i do wait for the plenum to refill and also have my first reg at 140 and second on 100. Also am shooting fx .22 atomic at 15.9 grains not sure why new to pcp but was told to have 140 for first and 100 on second dont know if it's just the tune.
FX Fps all over the place fx maverick
- Thread starter crowkiller15
- Start date
Have you adjusted your hammer spring or internal hammer spring at all? Sounds like you have the hammer strike too hard.
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I had a similar problem but with a .177.
IMO for .22 the regs are too low and (possibly) the hammer spring is too high. The dwell time on the plenum filling is instantaneous so I don’t think you need to wait.
Bump the regs up a small amount say, 125-130 low side and 150 high side bar to start. Don’t worry about the speed until you get the shot string flattened out then you can back off the hammer spring to lower velocity if need be.
unlike other brands I’ve owned, FX AMP regs do not respond within a few shots. Mine took close to a dozen before it settled in.
Also, there are specific instructions to adjusting the regs found in the manual. Re-read and follow closely. Would hate to see a reg damaged.
Best of luck!
IMO for .22 the regs are too low and (possibly) the hammer spring is too high. The dwell time on the plenum filling is instantaneous so I don’t think you need to wait.
Bump the regs up a small amount say, 125-130 low side and 150 high side bar to start. Don’t worry about the speed until you get the shot string flattened out then you can back off the hammer spring to lower velocity if need be.
unlike other brands I’ve owned, FX AMP regs do not respond within a few shots. Mine took close to a dozen before it settled in.
Also, there are specific instructions to adjusting the regs found in the manual. Re-read and follow closely. Would hate to see a reg damaged.
Best of luck!
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I wouldn't raise the reg pressure. Adjust the hammer spring and find the knee . Get it shooting consistent first then you'll know if you need more or less reg pressure for your target fps , 850-920 for 15.9g Atomics for me . If your not sure what the knee is then do some more research on tuning and make sure you're turning the HS in the correct direction. Try less HS first like Mongoose recommended . If you get into shooting pellets over 18gr you will want more hammer weight.
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Definitely a tuning issue. I have an m3 600mm barrel with second reg set to 70 bar and getting 900fps from the 18gr .22s. Watch some tuning videos or have your dealer tune it for you.
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internal hammer spring too light, probably not even engaged, thats what the issue was with my "tuned" crown.
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I'm going to guess you are new to PCP's? Let's start here and we'll get it figured out. Where are you located?
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I did but don't you have to adjust it to get faster bullet velocity since I'm trying to get it to 880 fps?
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Well idk how i would when I was adjusting the regs the first reg was fine but then on the 2nd reg I was setting it to 100 and I almost backed out the screw to where it's almost flush if I were to try to add more pressure to the second reg idk how I could be able to
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You shouldnt need to back out the reg nearly that much and risk damaging the reg orings. You can only turn the screw about an 1/8" at a time fyi and then need to take several shots for the reg and orings to settle in. If you adjust too much at once you can tear the tiny orings and cause a reg leak. But there have been more than on FX with the wrong piston or Belville washer stack to leave the factory. You are probably missing a washer, an AMP reg can get to ~180Bar in stock form (but shouldnt be set that high).
But anyway it would be good for you to do some studying on the balance of reg/valve/hammer when tuning a pcp. I would lower the internal hammer spring (IHS) adjustment, pretty much all the way and start from the known bottom of the hammer system. Keep your power wheel on the max when testing. Shoot 5 or so pellets through your chrono to level the hammer spring out and get a good fps idea. Then up your IHS a couple turns and re-test fps with another 5 pellets. Keep doing this until you see the fps stop increasing, and then back down the IHS about 5% of your fps. That would be the peak hammer system balance for that particular reg setting. Then if you want to change your final fps you can increase or decrease the reg and then re adjust your hammer system. Erratic fps spreads like you posted are almost always caused by either too little or too much hammer strike. Since your fps is already kinda high my guess is you have too much hammer strike. Kinda tough to explain all this in a forum post, but that will at least get you started. And here is a good video that might help you out too:
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Looks like regulator creep / balance valve o-ring stiction issues...unless that erratic behavior is at all times and not just after a period of sitting.
-Matt
-Matt
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Is your barrel oriented to use the pellet power port or the slug port? If you are trying to shoot and or tune with those pellets using the slug port you are in for a lot of frustration.
Also, as others have stated, you may have too much hammer tension.
Check which power port is in use then start tuning with the internal hammer screw almost all the way in. Shooting the 15 gr pellets you don’t need much plenum pressure and not much hammer tension either.
Best of luck to you.
Also, as others have stated, you may have too much hammer tension.
Check which power port is in use then start tuning with the internal hammer screw almost all the way in. Shooting the 15 gr pellets you don’t need much plenum pressure and not much hammer tension either.
Best of luck to you.
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I agree with what mongoose said. Turn the internal adjuster screw all the way in clockwise, put the wheel on 7 and shoot a few. Should be low velocities. Then start working up (counter clockwise) until you find that plateau in velocity. When you get near that plateau that is the maximum velocity the gun will produce at the set reg pressure. Around the plateau is where you will see the shot to shot velocities get really consistent.
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You said you have to wait for the pentium to refill. You also said you had the reg screw almost all the way out, what was your pressure then? It was asked is your transfer port on pellet or slug? Slug will give you a bit or erratic action but not like that.
You stated that you have 140 on #1, how did you test that?
This will tell us what your regulators are doing. If the regs are fine then you get to have some real fun......
Remove the adjustor, watch out for the little ball in there, it'll try to hide from you, work over a large soft towel. Remove the spring and check it, tilt the gun up and down is the hammer moving freely? If so, then give it a squirt of Tri-Flow. If not you get the pull the trigger and pull the hammer weight to see if it's badly scored, that happens if you've fired the gun with the cocking level back. With the hammer out, IF necessary, inspect the inside of the housing for broken parts, been there done that. Use some grease, real grease on the ball and the adjustor, it's soft aluminum. Orientation for reassembly doesn't matter, remember that little ball will try to run and hide. Oh, set your HSA to 19,3mm overall that is the factor starting point, too far out and you wouldn't be able to cock it.
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I'm gonna be honest I understand but am terrible with directions I would ask for someone to walk me through it but I wouldn't imagine you guys would wanna do that lol soo I'm gonna try to follow but we will see lol.
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We would love to walk you through it but like I said it is waaay too much info to try and convey in a short forum post. Watch the video Steve made that I linked above.
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Did your airgun come with a manual? You need to learn how to adjust your hammer spring tension first . Not the dial but your internal hammer spring. Put the dial on 7 and only adjust the IHS when finding your peak velocity then back it off some more max efficiency. Did you buy it used ?
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No I got it off of someone and I have looked at multiple videos and have adjusted my Hammerspring and plenum and the gun did have some problems which I have fixed correctly but I am unsure if the gun is having issues due to what they did.
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