Final answer:
In basic marksmanship, bullets are sighted to compensate for gravity, which affects how far below the aim point they will hit at longer distances. A higher muzzle velocity results in a flatter trajectory, reducing this drop, while air resistance increases with velocity and works to decrease the bullet's speed and increase drop over distance.
Step-by-step explanation:
The two most important fundamentals of basic marksmanship are grip and stance, and trigger control & sight alignment. However, to directly answer the question, regarding the physics of a bullet's trajectory when a gun is aimed at a target at a different range than it is sighted for:
- If a gun is zeroed (sighted in) to hit a target at 100.0 m, and the bullet travels with a muzzle velocity of 275 m/s, the bullet will hit lower when aimed at a target 150.0 m away due to the projectile's arc and the effect of gravity over a longer distance.
- Larger muzzle velocity would generally result in a flatter trajectory for the bullet, which means that the bullet would hit closer to the aim point at a longer distance than with a lower muzzle velocity.
- The effect of air resistance would be to slow down the bullet, causing it to drop more over a longer distance, and it becomes more significant at higher velocities.