Matrix Reinforced Ver.2 8mm Gearbox for Airsoft AEG by JG

"This is an update to my last one, this gearbox is amazing and i will run it in every gun, it takes alot of time to sand down to fit and function in the gun but the sheer durability is totally worth it, I'm running a 450 fps dmr no problem and they're isn't anything with the gearbox.

"Just got one of these to replace a old broken gearbox shell and let me tell you this thing is a tank...it is definitely HD. Now with that being said you will need to order a set of gearbox screws because it does not come with any. The other thing I would recommend is soaking this gearbox in solvent or paint remover. You need to get all the black paint off or you will never be able to properly shim the gearbox. Because of the inconsistencies of the paint when you tighten the screws the gears bind up. So far after removing all the black paint inside and out it seems to be good.

"First, this is my first gear box build. I am redoing an old Dboys SCAR-L and the factory gear box split at the end due to a heavier spring (m120 or m130 I believe). I ordered this after being told it will not fit, well it does fit just fine, but there were some modifications to get it to work. The loop just in front of where the trigger goes needs to be ground off externally. Internally I had to do more work. I had to lightly sand each of the bearing holes to get enough clearance get them to seat, could be the bearings were oversized, but not likely. There is no inner elevated pin where the trigger switch should mount, I used a bit of metal and JB weld to put one there and it worked, there is a tiny pin hole to center it. I had to shave a touch off the trigger to get it to reset far enough to catch the trigger switch in semi-mode. The spring guide is a swappable style, so the factory one needs some adjustment or a new one needs to be purchased to fit it properly, I do like being able to remove the spring, no exploding gear boxes due to the tension. I also cut a small window by the pistol grip to be able to shim the gears and see in there. All and all, with a little fit and finish work, it installed well. Just be sure to lube everything and you should have along life with it. If you are using a SCAR, the ambidextrous safety is compatible with this gear box as well without modification. 5 Stars would have been if it needed zero internal modifications to fit.