If the aftermarket plating included the cylinder and yoke, then the plating on both surfaces may be causing the assembly to bind, and not rotate properly.
I would suspect that the plated gun may have had fitting issues before the plating was done, which only made the issues worse.

Have you had the action examined and evaluated by a qualified, trusted gunsmith? Diagnosis of the problem will be much easier having access to the gun itself.

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Ret. LE, FA Instr, S&W Armorer