Selina stops the person aiming at her head from shooting her by placing her thumb under the hammer, but all of the rest of the guns are "hammerless."
When Selina is tumbling on top of cars while Bruce walks alongside her,,the handle of the whip on her waist gets visibly stuck when she tumbles over the roof of the car stopping her momentum before it cuts to her standing up fine.
The revolver Selina has is fired twice during her fight with Ecco, even though it only had one round in it for Jeremiah's initiation game of Russian roulette.