Hard to close on a fired case?
Well, that's because the case has expanded. It does that after being fired.
Hard to open on that fired case?
I suspect the pressure is too high. Inspect the spent case. Has the primer been flattened? If so, don't shoot that ammo anymore. The pressure is too high. Switch ammo.
Vigilantibus et non dormientibus jura subveniunt. Molon Labe!