Well, while not a significant factor on the path of the bullet in these cases, as the bullet drops and gets closer to the earth, the force of gravity does increase.
whether a bullet is dropped by hand or fired horizontally it will hit the ground at the same time. trajectory and travel time to the target makes the difference on where. i think....
There’s also the matter of the gravitational pull that the bullet exerts on the Earth. But, that’s a little beyond the scope of the article.