MarauderAirRifle.com

I decided to try the bstaley tune yesterday with my .22 gen II marauder,I installed the three o rings and start tuning with my stroke (i left the hammer spring tension at 1.5cw) i start from 2cw stroke and slowly turns clockwise till 5.25 where my velocity was in the 790's between 2200-2400 psi and left it there(My goal was 800-830 fps for 40 shots with 2800-1800 psi) as i was afraid putting the striker to long and was hoping to raise my velocity a bit using the hammer spring. So i adjust the hammer spring to 3.5 cw fill up to 2800 psi and shoot a string. The result surprise me, i was getting only 10 shots from 2800-2400 and shoot it down to 1700 with 40 shot my string start at 809 peak at 827 and was within this rang till about shot no 33 afterwards velocity keeps falling and at my shot no 40 it was 764. I was most efficient within 2400-2000psi it is where my 20 shots were. It is also at this preesure i was adjusting my stroke and was expecting more shots from 2800-2400 which i dont get.

What seems to be wrong with my set up?

Open up the velocity screw and start again.

Roger

I have open up my velocity screw at max

what weight pellets are you using?

Jsb 18.13gr

viewtopic.php?f=13&t=7275

Ray

i turned my hammer tension to 3 1/8 cw and shoot a string from 2800fill down to 1600
1 780
2 771
3 771
4 762
5 776
6 778
7 787
8 785
9 785
10 787
11 785
12 780
13 785
14 785
15 795
16 783
17 780
18 785
19 783
20 785
21 783
22 787
23 785
24 792
25 792
26 795
27 790
28 780
29 800
30 783
31 778
32 778
33 804
34 797
35 783
36 783
37 780
39 780
40 778
41 776
42 774
43 771
44 769
45 765

Thanks ray for the link.

I read your steps on bhb modification, maybe i have to add another o ring as i turn more clockwise my velocity drops. But first i'll check my transfer port and see if it has moved.

If anyone has any suggestion based on my settings (Hammer stroke 5.25 cw Hammer spring 3.125 cw and vs 4.5) and my shot string which i post above......Your most welcome!!!!

That setting should get you a much higher fps. I wonder if your hammer spring crapped out. Have you tried replacing it?

I've been having it for roughly two months, never thought i'd had to change it. Btw i check my vs and open it up to 5 ccw and here's my string with the same fill, HS and HT.

1 778
2 790
3 787
4 792
5 776
6 778
7 800
8 795
9 792
10 790
11 787
12 804
13 804
14 800
15 809
16 802
17 820
18 830
19 795
20 820
21 812
22 825
23 820
24 827
25 812
26 822
27 822
28 827
29 817
30 814
31 814
32 820
33 814
34 814
35 807
36 809
37 804
38 804
39 807
40 804
41 797
42 809
43 797
44 802
45 800
46 790
47 787
48 776
49 776
50 767

'npunk42' this string was using the ufc pro chronograph