problem with (seal?) in my ics sig 551

[Mongrol]

Not sure what it is but with a 350 fps spring its shooting 190 fps but when i take apart the gun and hold the barrel tight against the gun, thats when it shoots 350. the problem is that as soon as i let go of the barrel, it pops forward again and the fps goes back down. any body have any idea how to fix this?

[110]

There is a spring that rests on the front of the hop up unit that pushes the hop up unit off the outter barrel/chamber onto the gearbox.

[Mongrol]

should it be visible? i dont see one right now. i noticed that when i put the mag in it holds the barrel forward and i have to press pretty hard on the barrel to get it back in the correct place. When i press it the mag moves too.

[110]

Yup. you're missing it. Check inside the upper reciever. Might be on the outter barrel, if not. Contact ICS or jerry rig one from Ace.

[Mongrol]

Just checked and it doesn't have it. Thanks for the help