You’re right, 5th edition.
p. 205
I haven't read earlier editions, and the consistent mentions of Power Customs parts throughout was actually a little odd. It does diminish the integrity of the whole work a bit if Ron Power was the primary writer of new material and did significant other editing in the edition published after Kuhnhausen's death. Putting a photo of himself in the book and the almost exclusive mentions of his own products (no others immediately come to mind apart from Brownell's stuff) without being transparent about his editorial role is pretty weak sauce. I might have to dig up an earlier edition.Further regarding recent S&W firearms manufacture- it must be stated that more than 60% of the new S&W revolvers received and examined by author prior to publication of this manual have had mechanical problems that, on inspection, were so obvious that these revolvers should never have been shipped by the factory in the first place.
But to the point of the defect rate, I don't find it incredible on the face of it. There's a big gap between a gun that will go bang when the trigger is pressed (versus not going bang) and one that passes a complete armorer's mechanical inspection. Look at Dagga Boy's comments about the percentage of 1911s that will pass a complete armorer's inspection and functional tests out of the box. It's very low, and yet they almost all go bang and function well enough that most owners are oblivious. I'm not a trained armorer, but I'm two for two (one S&W, one Ruger) on new production revolvers going home before ever seeing range time, and I've looked at many others that were disappointing by the most minimal of standards in stores. If seriously gnarly burrs on the ratchet count, S&W seems to be close to 100 percent lately.