Tuning Baby Steps

Tuning a PCP with a balanced valve is a delicate process for sure, nice job!

impact m3's are a piece of cake to tune.......
"edit" (this is for pellets)

1. start with the valve adjust out past the 4th line,and leave your wheel on 16.

2. turn 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 10-15fps
(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.

starlingassn said:

impact m3's are a piece of cake to tune.......
"edit" (this is for pellets)

1. start with the valve adjust out past the 4th line,and leave your wheel on 16.

2. turn 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 10-15fps
(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.

View attachment 404327

View attachment 404328

Click to expand...

Always curious on how others tune, thanks for sharing!

I like to "fingerprint" a PCP for a particular projectile...

With the valve dwell or transfer port full open, I'll start with 100 bar on the reg and minimum hammer spring I'll increase the hammer spring tension and shoot until I reach the flat of the power curve and note that setting. Then I'll increase the reg pressure by 10 bar and repeat the process until I get to 150 bar.

Then I can plot the points on a "Knee Graph" knowing that my option velocity will be 5 to 7% less.

One I have a couple of Knee Graphs for an airgun I can see how the system is reacting and make a good guess at what settings should get me close to a balanced tune.

I usually do this type of testing at night so I can check the projectiles stability at the same time. Setting your parallax focus to 35 yards and shining a floodlight diagonally across the the shooting lane (leaving the backstop dark) works well.

Cheers!