I had mine apart many times and never saw the part you talked about
But for the feeding problem, I am sorry to say that if you have that problem its probably your bad day. The one I had S&W built about 5 years ago and picked it up new. The first couple of boxes only failed to feed every now and then, once I got past couple of hundred rounds it turned into a piece of crap.
I was told to shot more rounds through it and it would clean its self up, no luck. Sent it back to Smith and they pollished the feed ramp, NO LUCK.
Had a good gun smith that has built a couple of guns for me NO LUCK.
ANd he really worked on it.
I know it wasnt the mags, My mags worked fine in a german one.
At 600 rounds it was just about 1 every mag fail to feed. This was with good Whinchester hard ball. I picked up 1000 rounds to last me the life of the gun.
I liked the way it carried and the size was great.
BUt it was a piece of crap.
There are a lot of people here that say that the S&W PPKs is a great gun, and I am sure that there are some out there, but if I found them for $100 dollars each, as long as I carried them, I would go gunless.
I will also say here and now that I am a Smith fan, and have 11 N frames and a mod60, which I got rid of the ppks and picked it up, I would suggest you do the same.
Personaly I am tired of hearing about firing a gun to break it in. Sure you need to test a gun by breaking it in making sure its reliable, this is where the PPKs fell on its face. I had a Mauser 380 that fired with no failures new in the box. Had a Back Up new in the box, and thats a cheep gun no failures new in the box.
Good luck.