What if you hit a road bump and all your bullets fall on the floor, one round in particular wedging itself under the brakes, where the driver of the vehicle either cannot hit the brakes and dies or fires the round when flooring the brakes causing them to be killed instantly?!?!??
On a more serious note, I like this idea. This would be very productive to develop and add and would allow people to flee a shootout quicker as they don’t need to refill mags before getting in the car in case cops follow.