The split cases look similar, but remember, I also have the gross expansion with a bulge.
Later today I will run a couple of magazines of new factory ammo through the PPK-S to see if there are any unusual marks on the brass. I will also be making chamber casts of the PPK-S and the SMC Hungarian to be sure of the chamber sizes.
A weak recoil spring can cause the problem I am having, but the PPK-s spring feels much stronger than the SMC does.
I will post the results of my testing.