While it is not one of the more exotic big bore guns usually discussed here, the little Quackenbush is an interesting gun.

I picked up 2/3's of one yesterday and need a little help with the remaining 1/3. It is missing the breechblock.

If someone has a breechblock and no rifle and wants to dispose of it at a reasonable price, I would be interested. Otherwise, if someone who has one of these rifles would be kind enough to post or e-mail some photos of the two sides and bottom of the breechblock it would be greatly appreciated.

I have a machine shop and the deHaas book with the drawings, so making a replacement is not out of the question, but a look at an original would be a great help.

Thanks in advance for any help provided. 

Thanks Froggie, I did check there, but not much joy. They do have a takedown nut, which I have already made, and a firing pin, which is academic if I am going to make the rest of the parts.