GHK AK GBB V2 VSR TDC Aluminum Hop Up Chamber

I’ve purchased several of these TDC units and all of them required very minor to tedious filing to get fitment for each replica. From slightly unaligned drilled out holes to not seating fully into the designated hop up/loading ramp area correctly at all which was halfway in only for one of them. What also happened was the grub screw that applies pressure to the hop rubber can get stripped due to tolerance of the screw hole being too tight. Speaking of stripped screws, the shiny metal ones that came with the individual sets decided to strip after a few turns so I stuck with the stock screws and added the included rubber o-rings from the set to those instead. With the various tolerances between different replicas, EXPECT to hand file or slightly bore holes wider since this isn’t a drop in from my experience. But once they’re properly aligned and installed, the bolt carrier travels smoothly over the unit. I’d recommend a coat of paint to touch up/add protection to the surface too since they’re untreated. On a positive note, the 3d printed hop up chamber fits fine on all three of my replicas and the spacer that’s in between the grub screw and rubber does its job. I’ve paired them with PDI VSR spec barrels and PDI 70 degree VSR spec hop up rubbers with a roughly 70% to 80% of the side nub removed so it doesn’t protrude into the feed ramp. If you want a drop in option, you may have better experience than me if your lucky or search elsewhere if you want a drop and go option like the Bow Master feeding ramp along with their hop up chamber or a TNT retro fit version plus their barrel but those are AEG spec barrels instead of GBB/VSR spec like this offers. If you don’t mind modifying parts and some time, give it a shot. Who knows, this may be a drop in for you. Good luck

The hop unit seems well constructed, sadly both of my units needed a file to fit since both of the screws that hold the feedramp in didnt fit at all! After fitment, the hopup works great.

i had consistency problems with the standard maple leaf crazy jet set for the ak, completely solved with this hop up. with the right bucking and the proper weight full auto isn't a problem anymore even at crazy ranges like 60 70 meters.