Other Barra Cowboy 1866 disassembly (and hopefully fix).

[Brian VT]

I got this gun and it wouldn't hold air. With the "bolt" open it would hiss air from the breech area when pumping. If I closed the bolt it would hiss from the barrel muzzle.
I couldn't find any schematics or other help with repair or disassembly so I just dug in. Hopefully I can find the problem and fix it. Will update if I do.
I didn't do as well at documenting as I thought I was, so feel free to ask me to clarify anything for you if and when needed if you find yourself in the same boat.
Here's where I'm at so far...

 

[Brian VT]

I removed both sides of the receiver. The stock stays with the left half.
Be careful with the "wood" and "brass" as they are plastic and will probably break easily if you force them. Take your time and wiggle them around and they will eventually agree to come apart.

 

[Brian VT]

Then I removed both sides of the forehand grip. Pry the "brass" clip carefully from the center tab that hooks inside the grip halves.

 

[Brian VT]

Then there are a couple screws to free the barrel shroud. My pics didn't come out well for that. Sorry.

 

[Brian VT]

Next I removed the screws that hold the trigger/safety mechanism. It slides out the back.

 

[Brian VT]

Then I removed the screws that hold the barrel/firing mechanism. It also slides out the back. It has a tight fit due to the seals. I drove it part of the way out by pumping the pump lever. Then I had to put the barrel muzzle on some cardboard so I could push hard enough to push it the rest of the way out.

 

[Brian VT]

The 2 o-rings in the last photo did have some damage that you might be able to see in the pic. I don't yet know if they were damaged during assembly and were the cause of the leak, or if I damaged them during removal. But they are the prime suspect at this point.

 

[Brian VT]

Then I removed the drift pin that is the pivot and attachment point for the pump lever and removed those parts.
I believe all of the o-rings are the #118 as stated on the Bara website as they all live in the same tube.

 

[Brian VT]

Just replacing all the o-rings and putting it back together should be easy enough. And it will probably be fixed (assuming those 2 o-rings are the culprit).
But I'm curious about the firing mechanism that is integrated with the barrel. I don't see any way to disassemble it for inspection/repair. I'm hoping to find a way to put air to it to test for leaks. I will post back here if I figure that out.

 

[Brian VT]

The above may look daunting and complicated but it's really pretty simple. I think the main focus on reassembly is getting the o-rings started into the tube without damaging them. I will probably sand the inside edge of the tube to be sure it's not rough and maybe even put a bit of back bevel on it so the o-rings can be started in with no damage.

 

[marflow 777]

so, one tip, get a magnetic part holder
you are a brave man, but it was broken so no harm could be done to it

good luck and i hope you fix the problem, and your plans are sound
we will wait for you to tells us if it worked

 

[rokonman]

Could the hex on the valve be there to remove it with a wrench? I can see no other reason for the hex.