Hi I bought a G&P M4/ M16 Hop-up unit to be installed in my JG M4 (JG Thundermaul) I brought my gun to Xtreme Tactics in Winnipeg to have it installed. A few weeks later I got my gun back, with the original hop-up still installed with a note saying "costumer purchased wrong item, hop-up could not be installed". I clearly bought M4 hop-up, but they say it doesn't fit...
Here is the link to the hop-up I bought: http://www.airsoftparts.ca/store2/in...roducts_id=304
Does it actually not fit? Or did the gun tech just not know it is compatible?
EDIT: The same thing above happened with this item: http://www.airsoftparts.ca/store2/in...oducts_id=1317
Is there anything I can do to make them fit?