Top Hat Adjust Numbers… For the Experts to Interpret

Hi all. After consulting with GLBJ, I decided to adjust the top hat. I will spare you all the gory details of the adjustment. However during the test I did notice a few odd things and would like you input.

Prior to adjusting my velocities averaged about 832 fps with the same setup outlined below (top hat out).

I set the top hat in as far as it would go. I started testing and when I hit the magic gap with the jump in velocities, I measured it. It turned out to be .085. My velocities jumped into the 900’s and seemed to stay there. I adjusted the top hat out a bit more and continued the test. Here is where it gets weird… Any gap larger than .085 my velocities started to drop? I repeated the adjustments several times (keeping the tank filled to 2700psi) and every time I adjusted the top hat out past .085 the velocities started to fall… I set it at .085 and put it away for the night…

This morning I set back up and ran a string of 20 shots for you guys to interpret.

Set up
.22 cal. Talon SS with shroud
12” Barrel
Preload set at 4-1

The Test
20 Shot String
14.3 Crosman Premier HP (non weighed, taken right from the tin)
Start Test 2700psi
End Test 2500psi
Low 885.6
High 919.0
Average 906.2
Extreme Spread 33.42
Standard Deviation 11.13
1 900.6
2 919.0
3 914.3
4 916.9
5 913.5
6 917.4
7 918.5
8 915.6
9 917.1
10 916.9
11 914.8
12 904.9
13 896.3
14 899.6
15 896.2
16 894.2
17 898.5
18 895.7
19 885.6
20 889.0

There were a few weird readings like number one… But, to me it looks pretty good. What do you experts think? Do the numbers tell you something that I cannot see?

Also, why would adjusting the top hat out past .085 cause the velocities to go down? This could also be a flaw in my testing method because as I saw the velocities drop (one shot) and I would stop and go back to what turned out to be .085 ( I was looking for the jump or rise in velocities not drop… )

Thank you