How does my tune look like and any suggestion?

[Mapuia]

Just got my .22cal gen II synthetic marauder tuned using unsorted 15.89gr jsb with stock parts using the following settings
Hammer throw 8cw
Hammer spring 4cw
Valve meter 2.75cw
And here's my 60 shot string. I started filling between 3200-3100gun gauge(2700-2800 psi on hill pump gauge) and shoot it down to about 1700 psi.
1 799
2 796
3 819
4 803
5 801
6 798
7 828
8 797
9 800
10 822
11 794
12 807
13 821
14 800
15 795
16 811
17 812
18 832
19 808
20 809
21 824
22 803
23 801
24 803
25 829
26 831
27 831
28 804
29 830
30 807
31 833
32 830
33 820
34 817
35 825
36 807
37 820
38 801
39 824
40 824
41 802
42 823
43 803
44 806
45 802
46 803
47 789
48 785
49 787
50 812
51 811
52 810
53 800
54 774
55 776
56 770
57 764
58 774
59 783
60 767
It seems good to me as most of my target range is within 60 yards and sometimes 70 yards (plinking/small game hunting). As i am using a hand pump I'm looking for more shots per fill. This is my first PCP and suggestion from more experienced users will be very helpful.

[npunk42]

Being that most of your higher velocity shots are happening around 30 shots in, you might try filling 2600-2800 to start. Are you hitting your mark consistently at 60 yards with this tune?

[Mapuia]

I have only tried 15 yards and i'm having quarter inch group. While filling 2600-2800 which gauge reading should i take gun/pump

[RayK]

Gun gauges are typically unreliable. I would use the fill gauge.

Your string is *very* jumpy which is unusual. Is your chrony set-up with good light?

Ray

[Mapuia]

I dont have an actual chronograph so i download chrono connect for iphone and used that for tuning and my shot string.

[npunk42]

that is going to be approximate at very best. Lots of variables recording speed with sound. I wouldn't change any settings till you got an actual chronograph. Then your readings will be more in line with what the norm is here. You know apples to apples.

[Mapuia]

I'll try to get my chronograph. I have not been able to find one here in India. Thanks for the replies anyway

[RayK]

Just fill your gun to 2800 and enjoy shooting it for about 30 shots. No need to overthink this - especially if you can't get a chrony easily.

Ray

[npunk42]

What Ray said. Actual performance is far more important than readings. Try different fills, you'll find a sweet spot where you hit more often than not at 60 yards. Have fun and keep us in the loop.

[Mapuia]

The things i noticed after i tune is that its more quiet but when i am filling it i have to put more effort to reach 2600.
30 shots seems good, reason is when i am shooting the sound what the gun makes till 30 shots is very clean (a clean sound of tung) and after that the sound becomes a little flat (somewhat like sphlaat). Is it a common thing???