Hi guys I have a WE Glock 18c its we wet edition it’s in good condition with very minimal ware internally it has a magpul speed plate, nine ball gas router & a upgraded recoil spring I think this is where the issues lie. 
It shoots ok on semi but when in full auto it seems to vent a fair bit of gas. I’m not sure if I should be using red gas to cater for the heavier recoil spring and I’m not sure if the hammer spring has been upgraded as it should of been with the recoil spring. It shoots at 300Fps 
Im not sure but I’m selling it cheap because of this looking for £55.00 collected from Birmingham or £65.00 posted via parcel force 48hr tracked and signed for.