WE G39 hop up adjustment tool: is there such a thing? in Gas Powered Rifles & Polarstar Posted May 23, 2016 · Report reply well, I was pretty sure that was wrong lol. Yes, a pic from someone else showed me where the best spot to access it is. I was thinking aeg hop up and trying to do it from the side. Granted the side would be much easier with gloves on. But now I know to go from the top. Its my first gbbr so I am learning one step at a time.