Robert;
I have a junker Pieper Modified Diana on which the bbls were in rather poor condition & ribs & forend lug were loose. This I feel was the result of gun not having a positive bbl check hook so upon opening, the bbls are stopped only by the forend iron contacting botttom of frame which puts a tremendous force forward on the bbl lug unless it is opened very gently. This is a hammer gun with double underbolts & Doll's Head, laminated steel bbls. I had thought about trying my hand at re-tubing it for practise & got far enough along to put a propane torch to the joint. As I heated I noted that the melting solder did not form in the rim recess but instead began to form a ring in the mid-chamber area. I have no actual evidense of the tubes being threaded though. In the 1911 "ALFA" catalog is pictured a set of bbls of another brand with the short length stubs for fitting to a mono-block which are threaded. It was I felt a possibility Pieper used the same processs.
As to the patents, at present I only know how to access US patents. I wouild greatly like to know how to acess other countries patents. Any help you could provide along those lines would be greatly appreciated. Otherwise I could PM you my e-mail for the ones you mention.
Edited; Typing Terrible!!
Last edited by 2-piper; 12/02/07 11:35 PM.
