This will be in a HK416A5 by VFC Build List: Lonex Compression SHS 15-tooth FMR Piston Tienly 25k 22TPA Motor Gate TITAN Advanced MOSFET So my questions are as follows; I’m looking to stay around 400FPS with a .20g BB, what spring would you recommend to achieve that? Also, does Siegetek factor in the fact it’s a DSG when stating ratios? So are their 14:1 actually 14:1 or are they 7:1 in terms of the piston? And is it worth it to go with a Retro Arms GB or should the stock one be fine?