SACair Forum

OK... I have a PDI 130% spring which is supposed to get around 370fps and a JG G36c spring which is supposed to get around 370-380fps... Which one should i put in my V2 mp5 gearbox? The PDI spring is alot harder to get to fit into the gearbox than the G36 one. Does spring length have anything to do with fps?

it can, but not always. differance in wire thickness. more tension, more alot of things. If they both give u the same fps try the easier one first and see.