In the 2009 edition of Custom Combat Handguns #60 by Harris Outdoor Group there was an article by Dennis Presbrey where Cylinder and Slide shortened and removed the lug on the barrel of a M586 for him along with several other modifications. Perhaps you can get a back issue from them. Their E-mail in the magazine is:
[email protected]. Hope this helps!! Lots of good articles in that magazine. The gun came out pretty nice also!!
Jim