Because your questing is about air pistols and not an air rifles I'll stick to pistols. By the time you read this something new will have come along. New records are set very often. So I'll give you a general idea of one of the highest velocities that I know of. It's the "Evanix Hunting Master AR6."
It a Precharg Pneumatic gun (PCP) that fires a .22 cal pellet at 1000 feet per second. You need a Scuba tank to charge the pistol. This will give you enough power to fire all 6 shots.
A regular pistol is a firearm. It uses gunpowder to fire a bullet. An air pistol uses compressed air to fire a pellet with less velocity than a firearm.
The velocity of light is highest in a vaccum; slightly slower in air, and a LOT slower in water.
That would most likely be the Hatsan AT P2 PCP Air Pistol at 870 FPS
A the highest point its velocity will be zero.
The vertical velocity is zero at the highest point. It has ceased moving upward and will begin moving downward. Gravity and air resistance will have negated the original vertical velocity (y-component). So the velocity at the highest point has only a horizontal or x-component.
Sound velocity is greatest in solids, and the solid with the highest velocity of sound is metallic Beryllium.
Gamo Hunter Extreme 1650 FPS - Air rifle .177 Cal Air Force TalonP 900 FPS air pistol .25 Cal Hatsan AT P1 Air Pistol .177 870 FPS The Air Force TalonP is faster in .25 Cal than the Hatsan .177 Cal
It will shoot pellets or bb's. They normally use an air cartridge.
The most powerful air pistol would be a Air Force Talon-p 25 Caliber. This is a PCP class air pistol. The air tank uses 3000 PSI to fire the pistol.
Air velocity in ventilation systems
The ball has the highest gravitational potential energy when it is at its highest point in the air, as that is when it has a velocity of zero and is up the highest.
the velocity of sound in the air is 300m/s