Ok so I found that websites sell piston sets for this gun with two different spring options.
One option is 190% spring and the other is 150% spring. Obviously the 150% shoots lower
but I'd like to know if it's under 350 fps. Or maybe the stock gun is the 150 and this would be a waste of money. Does anyone know what 150%
actually means when it comes to fps?
http://shop.ehobbyasia.com/g-p-m870-piston-set-a.html