Q: Why do the factories load .22 target ammunition to lower velocity (about 1100fps or 335m/s) compared to hunting loads?
Some .22 Long Rifle cartridges have velocities of 1400fps (427m/s). You would think the faster the bullet got to the target, the more accurate it would be.
Robert Holman
A: The reason why .22 target ammunition has lower velocity has to do with wind deflection and drag. Wind deflection is not controlled by time of flight, but by the loss of velocity during time of flight.
In the transition velocity range above the speed of sound (about 343m/s or 1125fps), the drag increases disproportionately higher than the velocity increases. In other words, if the velocity is increased by a small amount, the drag increases by a large amount.
This situation is unique to that velocity range. At all other velocities, an increase in velocity will bring about a decrease in wind deflection, but not in the upper transition range.
This is the reason for the special .22 Match ammunition being loaded so it will not go fast enough to get into this velocity range.
The high-velocity .22 ammo has a flatter trajectory but is deflected more by a crosswind. Air resistance is much increased in this velocity range and a lot of air turbulence and pressure changes occur. The drag is affected out of all proportion.
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