The Xisico XS60C. Do You Want Maximum FPS or Maximum Ft/Lbs?

Above, the Xisico XS60C air rifle.

"Everyone" - or at least many people - want the maximum possible muzzle velocity - FPS - from their air rifles, believing that this is best. But is it always?

Pellet weight can play a big part in determining the muzzle velocity achieved by an airgun. Different pellet weights can produce significantly different muzzle velocities in the same gun, with no other changes.

The other major factor to be considered is muzzle energy - Ft/Lbs. This is the "hitting power" of a pellet.

A higher muzzle velocity - FPS - might be best for a flat trajectory and maximum range, but the highest muzzle energy could be most desirable for hunting where a "one shot clean kill" is desired.

Let's look at the muzzle velocity and muzzle energy results achieved from testing a .177 caliber Xisico XS60C air rifle.

Here's the test data for a .177 cal Xisico XS60C shooting a variety of pellets. (Click to enlarge).



Now, if we take this data and graph the results, we find that the lowest weight pellet shoots the fastest. No surprises here!



Yet, if we graph the results for muzzle energy, we find that the slowest, heaviest pellet gives the most muzzle energy, or "hitting power".



So what should you choose - maximum muzzle velocity or maximum muzzle energy? Or a mid-point somewhere?

It's your choice, dependent on the type of shooting you do. But it's good to remember that the highest muzzle velocity is not always the best if you're hunting and aiming for a humane "one shot kill". In this case a heavier pellet, traveling slower, could be a much better solution than a lighter pellet traveling faster.

To take an extreme example. Would you prefer to be hit by a very light ping pong ball traveling at 500 FPS, or a 24 Lb cannon ball traveling at 50 FPS? I'll take the light, fast ping pong ball any time, it's WAAAAAAAY less dangerous, even though its' muzzle velocity is much higher.

This data applies to the Xisico XS60C air rifle. But the same principal applies to any airgun. Maximum muzzle velocity sometimes may be the best solution, but not always. It depends on what you're aiming at when you pull the trigger.