Fx impact m3 700mm 6.35 - JSB Knock OUT

Hello , im Alex from Bulgaria. Order Fx impact M3 .25 with 700mm standart stx liner + heavy one. At the start i will use gun fully stock.
My question is:
- Can u tell me some TESTED tunes exactly on this setup - Impact mk3 .25 with 700mm liners with JSB KO mk2. My wish is to have maximum velocity and nice groups in 50 and 100 meters. Will be easy if i tune gun not from 0 :)