DMR problems:

[Gills]

Hay everybody.
I have 0 clue wtf is going on with my new gun.
I made a custom made DMR sniper. with a TB barrel and good upgraded gearbox.
I put it all togethor, and i cleaned out the new barrel with some silicon oil and paper towel, and when shooting it, the BBs are only going 5 feet. The gearbox is giving me great compression, i think it is the barrel but I dont know.
I ran the barrel with lots of paper towels making suer it was dry, now it gives me about a good 20 feet. could this be the barrel? or the hop up? or what went wrong?
any help is appreciated, thanks much

[AxisOfOil]

Hop-up bucking.
Hop-up.
Nozzle.
Gear-box fatigue.
Receiver fatigue.

If your bucking is torn or not sealing, you get shit compression. Period. Check it. Replace it anyways (DMRs can always use a new bucking)
If your bucking has wrapped around the back of the tbb into the way of the barrel, this can cause exactly your problem. Sounds like you already looked at this though.

Hop-up unit - If it's leaking air either out (if it's broken) or down through the magwell (If both your nozzle and hop-up are worn pretty well), or in any other direction... you get crap compression. This probably isn't it if you're not getting much distance... as it's USUALLY a small leak.

Nozzle - If it's worn significantly, it won't seal into the hop-up, or will strike the hop-up unit and not fully cycle, this forces air out of every part of the hop-up, and then uses what's left to overcome loading the bb past the bucking's rear-most part (the skinny part that keeps you from double-feeding).

Gear-box fatigue - If your gearbox is stretching a bit (can happen... it's more likely to break though), you can get massive compression failure when you cycle the gearbox with a motor instead of checking compression by hand at the cylinder.

Receiver fatigue - If your gearbox isn't being held in place properly, and is slightly moved backwards from the hop up unit, it will cause the same leak as described with the worn nozzle. Once again, this is highly unlikely, but possible.

And, of course... check your compression in the box again.

[clayton]

maybe you just installed the bucking at the wrong angtle

[Gills]

When I get my motor in, i plan on heading over to the Gearbox in pheonix to check it out. im thinking it is prob the hop up or so. Ill also give them my kwa to check it, its been giving me problems.