I'm not an expert on Parkerized service firearms but Parkerization is generally reserved for the frame, not the internals. The barrels have never been Parkerized, as far as I know. No need to do that to internals or the barrel. adding the additional layer of finish actually makes for tight fitment which can pose some problems.

I wish someone who knows a lot more than I do about that finish could chime in. Something is a little unusual with the finish that needs some 'splainin!

But, it should be tight and probably shoots well. Remove the extractor and firing pin and make sure those channels are clean and oiled well. Gunk gets stuck in those areas that can alter functioning.

But, take her out and put some 45s through her for a good testing.