Just got off the phone with Smith customer service. The gentleman initially said the "F" designated a K frame gun, didn't have any idea what the "V" stands for. Put me on hold and then came back with that it's not done anymore but it had something to do with identifying the cylinders during the assembly, pre-finishing.

He said Roy Jinks would probably know but he's out this week and if still interested to call back next week and ask to speak with him.