MP5 firing problem

[1ndigo]

So here is the problem, my TM MP5 SD6 which is stock will not fire a few times when I pull the trigger and then when it does fire about three BBs will fall out of the barrel about five feet away.

However, sometimes when I pull the trigger the BB will come out but it will go again all of its fivew foot range. Not all the time though, because about ten percent of the time the MP5 will fire properly and the BB goes out on it's flat trajectory as it would normally fire. I have done this with my low capacity magazine and high capacity magazine (both TM) and the MP5 reacts the same way with both of them.

I bought this gun slightly used from a buddy of mine who joined the navy and needed money not too long ago. When I took this gun to a gun doctor he said that there was lube all over the place inside of it and it was apparantly car grease or lube of some kind but they did something to it and it fired fine for about five games. Could it be as simple as removing the lube from inside the weapon and re-lubing it with proper silicon oil or could it be something far more sinister?

[DarkAngel]

There are many different possibilitys that i can think of.

First, the BBs you are using might be a factor depending on the quality. Uneven, deformed or low quality BBs can cause your bbs to have friction in the barrel and get caught. the other possibility is that the lube could be getting on the bbs. If the lubs is viscous enough, they would also act like a sandtrap and stop the BBs in the barrel. the other possibilitys is that your hopup is set to high, your hopup rubber could be ripped and the BBs are catching on it. or your losing your seal between the hopup, and the cylinder or the cylinder itself may be leaking. Theres no way to be sure without seeing it up front

It sounds to me that BBs are somehow not leaving the barrel properly, and are getting wedged in tight enough to stop the motion, but enough to allow it to be unwedged when another bb hits it, or is forced behind it by the loading nozzel. Kinda like the billiards effect.

[safx]

Turn the hop to zero first, if nothing changes check the hop rubber for deformities. If there's nothing wrong with the hop area, your tappet plate may be busted and not moving back and forth to seal before each shot, letting 3-5 bbs pile in before there barely enough air seal to shoot them all out 5ft.

Good luck

[1ndigo]

Alright thank you for the responses.

I am going to open it up and check those parts.