Here is my 5903TSW marked G.C.D.C. and my understanding was it stood for Gwinnett County Department of Corrections. It came from a dealer just outside Atlanta and since there's been a good amount of SW Auto's coming out of the area around there it looks like the agencies there did a large group buy of them. Since it's a TSW my thought was these were for a special response team or something but the Probation Officer or Bailiff issue weapon is a good argument too.
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I also have that 6906 that's marked G.C.S.D. 50 and am working on getting a letter submitted to help trace that one to a department. I usually use an acronym searcher to start my locating of these marked guns. Then I start googling departments and counties looking for history sections and old photos that if I'm lucky can show a holstered weapon or a range session.
Of course my new 6904 just has 5 numbers engraved so more work needed for that one.
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