Version 3 mystery, super gremlins, PLEASE READ
 

the gun

Echo1 Vss Val

the run down

upon inspection everything in this gun is wear free, cutoff lever is in mint condition, this gun has rarely been fired.

the problem

upon loading a magazine in the rifle and having bbs firing it will go on a mystery 3-5 round burst,

gearbox can be fully taken out the gun, selector put in the semi auto position, having as much as a finger touching the nozzle, the gun will go on a mystery full auto rampage.

why its weird
this problem is completely absent when you are dry firing.

sounds like a tigger contact problem
try replacing that part with another one
I have hade a few problems with those in version 3

blacksheep, its fine when i dry fire it, its only when you shoot it will you have problems, it is not the trigger contact, when there is more compression in the cylinder there is full auto..

How much tension is there on the cutoff lever? And does it move freely with the sector gear in place?
Im just guessing here but maybe the shock of the piston hitting the cyl head shakes the cutoff lever out of its spot.

Had a similar issue 4 years back or so. I had to sand the top of the trigger sled because it was getting caught on the release under the tappet plate.

check the switch prongs to see if they aren't grabbing the shuttle too tightly and check the tappet interaction with the shuttle and shuttle spring.

pesto was right