I have remembered a couple of other things on this subject...
My PM9's always scratch/chew up ammo that is cycled thru a a few times.
They also have a habit of seating the round deeper into the case (making overall lenght shorter).
Both examples of ammo battering are somewhat normal for auto-loaders, but the PM is harder on ammo than my other pistols and indicates a moret obtuse angle encoutered during feeding.
Anything that tips the nose of the round down further will magnify a feeding issue.
If the magazine is inserted before the slide is pulled back the nose of the first round is pushed down a bit by the bottom of the slide, if the nose doesnt pop all the way up before its pushed forward I suppose it can dive into the bottom of the feed ramp.
I never had it fail to feed if the slide was locked back before inserting the magazine and round #2,3,4... always feed normally.
