A.B.T gallery gun

[slow_runner]

What can someone. anyone(?) tell me about the ABT gallery gun?
I know of one that is coming up for sale and it would be helpful for him to be able to give some history to it. other than 'here it is'

What is stamped on the action is the following:
ABT Manufacturing Corporation. Chicago. Illinois. USA
There are a list of patents with the latest Patent application being 1949.

These gallery guns were designed to shoot 3/16" steel ball bearings.
It has been professionally modified to shoot standard, more readily available steel BBs.
The original 3/16" barrel and transfer slide are still with it to enable conversion back to standard.

I will put up an image when I return home this evening.

At this point I have not discovered much other than what is made known here.
http://www.crowriver.com/abt.htm

Thanks for your help.