Here is some Good/sad information on this little gem. I'll hold on to her until I can figure something out. I'm not wanting "fool" anyone.
Thanks for getting back to me JedClpIT.
I saved the image of the forcing cone and had a friend make some inquires to some knowledgeable S&W people.
Seems...
So, while trying to find a LH piston BCG for a Stag upper, I found out the difference between Adams Arms (top) and Stag's(bottom) piston bolt carrier groups. The striking plate ( where the gas key would be ) measures .173-5 inches closer on the Adams Arms. It was hard to get an equal reference...
Oh my, how well this response applies to the persuasion of people on topics well beyond forensic ballistics. For we are all human and fallible, even scientist and the " more learned than I ".