I just picked up a .25 cal M3 with a 500mm barrel. can you guys running the same setup please share your Tune Settings for jsb 25.39 and 32 grain pellets please.
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FX Fx Impact M3 .25 Cal 500mm Tune Settings.
- Thread starter miamiguy2017
- Start date
One of my M3's (my iguana gun) is set up the same. I am running the JSB Exact King Heavy MK2's at 910fps using Lab Radar. I am getting great accuracy and consistency. My settings are:
R1: 185
R2: 145
Macro: 16
micro: 4.75
valve: 4 line
ES: 8
SD: 2.5
Your settings might be different
Good luck
R1: 185
R2: 145
Macro: 16
micro: 4.75
valve: 4 line
ES: 8
SD: 2.5
Your settings might be different
Good luck
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Do you have a chrono? If not, I wouldn’t touch anything. Otherwise you’re just moving stuff around without actually knowing if you’re getting results.
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i know FX makes it sound like you can "share tunes"
but in reality it doesnt work that way.
my .25 M3 compact is the easiest gun to tune that ive ever owned.
but in reality it doesnt work that way.
my .25 M3 compact is the easiest gun to tune that ive ever owned.
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heres my........
"impacts are a piece of cake to tune"..........tune.
1. start with the valve adjust out past the 4th line,and leave your wheel on 16,
2. shoot and keep turning up your micro till your velocity stops rising.
3. click the wheel down 1 number at a time,
-or-
turn the micro down a few clicks at a time till velocity drops about 15-20fps
(since the macro and micro adjust the same thing,but do it in different increments,
you can choose to do either,
on my m3 it seems one click of the wheel = 4 to 5 clicks on the micro)
4. slowly turn the valve adjust in till velocity drops another 10fps or so.
5. enjoy your tuned impact or fine tune more if you wish.
do the same thing any time you increase or decrease regulator pressure,
to find a decent balanced state of tune.
"impacts are a piece of cake to tune"..........tune.
1. start with the valve adjust out past the 4th line,and leave your wheel on 16,
2. shoot and keep turning up your micro till your velocity stops rising.
3. click the wheel down 1 number at a time,
-or-
turn the micro down a few clicks at a time till velocity drops about 15-20fps
(since the macro and micro adjust the same thing,but do it in different increments,
you can choose to do either,
on my m3 it seems one click of the wheel = 4 to 5 clicks on the micro)
4. slowly turn the valve adjust in till velocity drops another 10fps or so.
5. enjoy your tuned impact or fine tune more if you wish.
do the same thing any time you increase or decrease regulator pressure,
to find a decent balanced state of tune.
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You start the tune with it basically out of the equation. It’s just used at the end to tie everything together so to speak. As far as 25.39 pellets I can tell you that with my compact maverick a 100 bar regulator pressure produces just over 900 fps with a good tune between hammer and valve. Probably a good regulator starting point on the m3.
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see #4 above.
the valve adjust is adjusted last,
it has a bumper in it that cushions the valve at the end of the stroke,
and it used to help flatten the shot string.
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Great advice laid out in an easy to read formula
I would just like to add another reason to start with the valve open all the way as described above by @starlingassn
If you didnt, and say you started your tuning with the valve stop adjusted at 2 lines; you can really caveman ram the valve rod and the bumper stop. It is possible to damage the valve rod assembly, and the stop bumper assembly if you slam it with a hammer strike that is too hard. By leaving the valve stop open you can safely and accurately control the last little bit of the hammer strike momentum.
And congrats on your Impact they can be a lot of fun and provide a lot of utility.
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