1077 bullpup mod

[BigErn]

Glad you got that figured out Zip. Now go shoot that thing and take some pics!

[ZipSnipe]

I am dying to go shoot but it is soooooo freakin hot makes it uncomfortable and not fun.  But I am hoping tomorrow will be cloudy and breezy. 

Plus I just got a new scope for it and need to dial it in.

[BigErn]

I am dying to go shoot but it is soooooo freakin hot makes it uncomfortable and not fun.  But I am hoping tomorrow will be cloudy and breezy. 

Plus I just got a new scope for it and need to dial it in.

Yeah Zip I know it's really hot in Florida. I'm in Miami. One of my favorite things to do is to sight in new optics on my air guns.

[ZipSnipe]

Well "dang"!!!  This gun is really starting to wet me off. So I load a c02 go to fire and again nothing, ammo clip was correct, trigger was correct. I can definitely hear c02 leaking.  Man I swear I am just about ready to send this gun to Big Daddy Joe and just let him tune it cause I am goin crazy!!!!!

[ZipSnipe]

The saga continues....

Ok got the valve apart and there is definitely a faulty seal as it goes over the firing pin very loose.  In fact I am looking at the seal (black rubber) which is press fitted into a brass washer and I am asking myself why not just make it a one piece delrin?  So if I have the drill and reamer for that size firing pin then I might give it ago.

But I did talk to Cameron over at Crosman and he said to open the valve and see what was defective and he would send me a new one.
  Left a msg with him so waiting to hear back from him.

[ZipSnipe]

Ok seal is enroute. And I will also try to make a whole piece out of delrin if I have the correct drill and reamer

[ZipSnipe]

Well bummer again !!!!

Ok called crosman told them about the hammer pin seal and I thought that it should be made out of delrin. Well guess what they sent me one made out of delrin. The problem is either the hammer pin is too small or the seals were too large.  The hammer pin is .107 in diameter, the old seal was .110, the new delrin seal is .123.  In my opinion the hole diameter of the seal should be .108 and no more.

So tomorrow I will call someone at Crosman and see if I can get an answer on what the diameter of the seal and pin should be.

[ZipSnipe]

Finally success!!!!!   New transfer tube and seals did the trick.  I believe it was the transfer tube that was causing the leak as it was .002 smaller in diameter than the new one. 

Such a sad story though to have to completely rebuild the gun for the manufacturer.  But they were very helpful and sent all replacement parts at no cost to me.  This weekend I will post pics and fire several clips before I past final judgement on if the gun is finished.   Thanx to all who have been keeping track and hopefully some will learn from my experience.

[ZipSnipe]

added some new pics new scope and scope mount

[Donny]

Sweet job Zip, this project turn out really nice, i think you should do a qb-78 next