Well, I have finally gotten down to looking at another 416D. This one is also a torque version, so it has the same gearbox ratio as mine. It is also from the same lot as mine, ordered at the same time and delivered at the same time from the same retailer, Double Tap.
Immediately upon arrival, I picked up the gun. The floppy gas piston is present in this one as well.
http://imageshack.us/clip/my-videos/...bitcwimvy.mp4/
The issue here is purely one of QC, and only a blind monkey with no thumbs could have missed this at the factory.
Here, you see the spring that keeps tension on the piston and guides, to keep it from flopping around. Please note the that the spring does not sit in the guide. The gap you see + the depth of the guide = the distance the piston flops around. Unacceptable.
The solution is to remove the rail, remove the piston assembly and stretch the spring. Why was this not done at the factory? This is how it should look. It was a simple fix, it is cosmetic only, but the result is a noisy rail section.
This particular gun also had a complaint of a poor hopup. The owner complained about terrible range, and I confirmed that with lobbing I could get the BB to travel 100 feet with the hopup fully engaged. The problem is the same as before, the adjuster cage is utterly useless. The cage was openned up due to no glue on the adjuster pin, the roller was a hard rubber that spins on the pin, and the spring does not offer enough tension. If you were trying to build the worst hopup possible in a TW, this is what you would do. After many years of modified hopups being available, any company with any sort of R&D would look at those and at least attempt to incorporate those designs into a gun claiming to be a superior option to Systema. FCC has not done this, and I have no idea why they would build a gun today with a hopup Systema designed and quickly discarded 10 years ago. This offering from FCC is a copy of Systema's Gen 1 hopup.
Please note the poor fit on the adjuster cage to the inner barrel. Even though the hopup was inneffective, had the adjuster rubber been better, the resulot would have still been wildly inconsistant shots as the cage flopped from side to side. What more can I say?
When I looked now at the lower, I noticed a couple of things. The buffer tube was threaded in one more turn, so no shims present. A stark difference from mine. The buffer cap was the same, it was replaced with a Systema buffer cap, and one shim added to fit the receivers properly.
When I looked into the lower receiver though, I saw this:
The rear gearbox fixing screw was fully undone. The wear on the screw is from the receiver hitting it. My first reaction was WTF, is the threading bad on the receiver like a kit I had done earlier? No, it simply was not tightened up. Whatever. But that lead me to wonder why. So, with the permission of the owner, I decided to remove the gearbox. The reason I asked for permission is because FCC has put seals on their gearboxes. I have dealt with this issue before in my job, as openning seals usually results in voiding warranties without permission, but it would appear I am not first up in this gang-bang:
Who openned this gearbox before me is unknown. Not that is matters to me, as long as everything is OK. Well.................
Metal shavings everywhere.
Again.
Extreme gear wear.
More metal shavings.
That awesome gear lash I have come to love. Now, this gearbox has not actually failed, but failure is immenent. Mine lasted about 8000 rounds until it failed, and by failed, I mean it failed to cycle and pull a piston under load, the gears would grind. This box had perhaps 1/4 of the round count of mine, and I would be surprised if it made it as far mine. So, the decision was made to pull it for return to FCC.