some numbers on my talon with 24

im using a 24 bbl with the stock tss tank
pw 12
th .062
3000 psi end 2800 psi
1-899
2-896
3-881
4-879
avrege 888
es 20 fps
kodiaks

pw 12
th .062
3000 psi end 2300 psi
1-951
2-958
3-955
4-954
5-950
6-951
7-948
8-943
9-939
10-953
11-940
12-940
13-955
14-937
15-947
16-936
17-929
18-939
19-946
20-925
21-924
22-925
23-937
24-923
25-920
26-928
27-916
28-915
29-913
30-925
31-909
32-909
33-924
34-907
35-904
36-903
37-907
38-898
avrg 931
es60
sd 17
jsb exact 16 gr

750fps 0 yrd-20yrd 705fps jsb exact
671fps 0 yrd,638 20 yrd , kodiak did this for bc calculation

any ideas why i cant get higer numbers? even with light pellets gamo match the fastest was 980 fps with the 12 inch bbl the highest i got was 750 with jsb and 670 with kodiaks