That's not physically possible. Either the trigger bar cruciform engages and retracts the firing pin FULLY as the slide returns to battery...or the firing pin isn't retracted at all. There is no half cocked possibility.The 33 does not re-cock fully...
What you describe is a light primer strike after the firing pin is released.
Ahhhh...there's the likely problem source. It is very possible that something in the coating process has resulted in resistance to the free low-friction movement of the firing pin in its channel in the slide. There is a thin polymer FP channel liner that lines the FP channel. It will not withstand the various coating processes. If it was left in place during coating it will distort and rub against the firing pin, producing light primer strikes.All stock except for the slide which has been coated with FailZero.
When the slide is removed, depress the firing pin safety plunger fully. You should hear and see the firing pin move back and forth if the slide is shaken. The firing pin should move in its channel with almost no resistence until you compress the FP spring as you retract the firing pin lug.
If there is no free movement, you have obstruction of the FP channel. If the channel liner is damaged, it must be replaced. That will require care to avoid damaging the new liner during installation, especially if the coating process altered the surface of the channel under the liner.
Other common tbings that can cause your problem:
1. Damaged Firing Pin Safety and/or spring.
2. FP spring cups improperly installed.
2. Debris in FP channel.
3. Damaged FP spring.
No. The coil trigger spring in the trigger mechanism housing was no effect on the striking force of the firing pin. A weak trigger spring would show up as a heavier required trigger pull, but will not change what happens after the trigger bar cruciform releases the firing pin.The firing pin still hits hard enough to leave a mark on the primer but not hard enough to ignite. You can feel it when it happens it just feels like a very weak trigger spring...
Check for problems in the firing pin channel, especially the FP channel liner distorted by the coating process.I have replaced it several times. Now has stock trigger spring now And stock firing spring. I have changed the trigger bar out...
FWIW, a "coated" Glock is very far from being a stock pistol. ALL coatings of Glock slides are unnecessary and harmful in both the short and long runs. Slide coatings of any sort are extraordinarily BAD ideas that disqualify the pistol for serious use as a weapon.