[acbianchi]

My NAA I presenting a weird behavior.

- When it is completely assembled and the hammer is down, the cylinder pin is correctly positioned holding it.

- When I pull the hammer, the cylinder rotates and the pin goes down, but do not return to hold the cylinder (it stays down) and the cylinder stays 'free'. If I put down the hammer, the pin goes up again and hold the cylinder.

- if I move the hammer very fast, the cylinder rotates fast too.

I have disassembled and assembled it again and again, but always the same thing happens.

Living in Brazil is a little hard to send it to the company at US.

Any hints to help me?

Thanks!

 

[JBelk]

I think your 'cylinder pin' is what we call a 'bolt' or 'cylinder stop'....the part that rises through the frame to lock the cylinder in place.
I have one here somewhere and will continue looking, but that part is usually operated by the trigger and has its own spring that urges it upward, locked the trigger pulls it down, unlocked.

 

[acbianchi]

Thanks for letting me know the correct name of the part. I tried a direct translation from our usual words.

I guess its spring is fine, as we can see the bolt moving. As far as I can see, what make it to move and lock the cylinder is the movement of the hammer, since it has a pin touching the bolt.

It would be correct that the cylinder stop stays touching the cylinder while this hammer is cocked or uncocked, right?

 

[JBelk]

It is part #7 and it lays just under the side cover. #16 looks to be a plunger with #15 a coil spring behind it. That could be the 'trip' for that part. Examine the end of #16 real close. I can't see how they cause the bolt to slip off that part as the hammer approaches full cock.
I don't have one here to operate but as I remember the cocking of the hammer makes the bolt go down so the cylinder can turn. (#11 is the 'hand' operated by #12 the hand or pawl spring. That spring is a week point in the design and often fails.)
The bolt should be down on the loading cock so the cylinder can be removed for extraction/ejection, but the bolt pops back up at full cock to stop the cylinder from rotation. Part #3 is the bolt spring. The arched part of the bolt seems to fit the #16 pin somehow for operation.

 

[acbianchi]

Thank you so much for the picture. I do have all parts as in the picture. But it seems that the problem is around the pin #16 and the spring #15. Do you think that this picture shows the pin and the spring should be inserted from the same side of the hammer? I put the spring on the right and the pin on the left (close to the bolt).
I understood everything you said about how it would correctly move. It is the same thing that I understand about this synchronism.

 

[acbianchi]

I just disassembled, cleaned, and assembled it again. I had to polish a little bit the bolt and now it is working properly. Thank you for the picture.