Usually my C9 will shoot any load that I feed it from dribblers out the barrel to hot +P loads.

The other day when I went out to test some 38 and 9mm loads I had an eye opener.

All the copper JHP loads ejected from 124 to 147 gr bullets but
when I tried my coated 115 gr. bullets, I had three fail to feed another round
or the slide not closing and the trigger not being able to pull.

I took the three rounds home for closer inspection, to see what was up.
These same loads in my PT9 5" work 100% from 1.08 to 1.12" OAL.

I found out that my C9 is finally picky on how you load the 115 gr
bullets from Gallant.
If they are just a touch over a 1.12" OAL............
and the belling of the case is not 100% level .........
due to their Ogive shape, they will not "Plunk" in my chamber.

I cranked down the crimp a touch and reseated the three rounds
plus a box of 50 that I had loaded for the family and all was well again, with the little C9 pistol.

It is funny how the shape of a bullets Ogive can have, on how it is loaded.
A Berry 147 plated RN bullet will plunk all day long in my C9 with a OAL of 1.16".

Just glad it was me.............
I though that maybe I had mechanical or trigger problems.

I made a note to seat these 115 coated to 1.10" for the C9, to prevent future problems
since they are just for target use and tin cans.

My wife's is also pretty much fail safe but we only feed it factory loads. It's her carry piece so we keep it simple.