Most interesting post about the neoprene shim on the magazine. I had not thought of that during my early smiley tests years ago. And yes, after many tests, I concluded that one of the basic causes of smileys with the P3AT was the cheap MecGar magazine. It's made with a slippery, black, epoxy coating and the ears at the top can't prevent the round from slipping forward during recoil of the first shot. It then gets hit just before chambering. (You can confirm this by extracting the mag after firing a shot and look where the top round is in the mag.)
I tried a bunch of stuff, grinding off the coating with my dremel, tightening the ears in a vise, putting a punch mark at the back of the ears, etc. And about all I did was ruin the magazine. Also, bought several replacement magazines and was surprised that some came with very tight ears and no smileys occured with those.
In fact the P3AT I have now, bought last year, doesn't do smileys. The magazine appears to be one on the low end of whatever tolerances Mecgar uses.
All this bull is listed on my smiley threads at USR, the WWW link at bottom sig line.
So if you still have some smileys, maybe try getting another magazine and see it it's better. I wish KelTec would just use a bare steel magazine without that slippery coating.
Mostly my opinion. But based on experience I hope.
Oh, note, Ruger's LCP uses the same Mecgar mag and the smileys I got from one I tried were much worse than any P3AT I've had. And I've had 5 P3AT's.
So, don't sweat the smiley problem. As long as your P3AT shoots good, no worry, (unless it's an unmodified 1st gen).
og.....'what? me worry!!