Originally Posted by Thenooblord
my old AK fed every BB from all of its mags, could never figure out why or how...
from conversations with a friend in HK, who knows his stuff..
'when the piston is retracted from the fully forward position, it creates a partial-vaccum infront of the air-nozzle, sometimes this partial vaccum is strong enough to pull a bb up from the HOP BB Feed tube'
some guns will create a greater vaccum (full-cylinders) then others, rate of fire makes a big difference as well as spring strength..
i would guess a stock (or near stock FPS) gun with full cylinder and a high voltage battery would generate the most..