There's still plenty that can contribute here... sometimes the chamber is not quite at SAAMI specs. For instance, if you're only about 1/16th of an inch short of battery, and you are using a gunpowder that leaves unburned powder particles in the chamber, in combination with a chamber depth that may only be a few thousandths short... bingo! that can cause the problem. If you're more like 1/4 inch short of battery, a list of possible reasons why would just be too long to print, but it could include the possibility that some klutz thought he'd make the slide easier for his wife to pull back by clipping some coils off of the recoil springs. Ultimately, a GOOD gunsmith may be your best bet. Particularly, one who is familiar with the Detonics pistols. There's nothing wrong with asking on a list like this, but there's really nothing better than for a GOOD gunsmith to have the gun in his hands when the malfunction occurs.
Hope this helps, ...Deeton