Popped a 20# recoil spring into the Firestar after finding the existing spring (allegedly 16#) was rather soft. The indicator was that even 115gr plinking loads were violently ejected. The new spring has tamed the recoil and ejection speed, although one round of 115gr WWB did not eject. 124gr ammo was flawless.
However, the gun still shoots low regardless of ammo, about 3 inches at 7 yards. I was very surprised that the POI did not change between the 115gr and 124gr. I observed the same phenomenon with my Star Ultrastar, so maybe it's a Spanish thing.
My other issue is that I tend to pull my shots a little right with the Firestar. I think my slim hands and long fingers may be a problem with this gun, which would be a great shame as it is great size for a carry gun. I don't have this pulling issue with a Springfield XD-SC, so it's not all small guns by any means.