Shooting FX Slugs And Pellets In An Impact
The new FX Hybrid Slugs are big news in the airgun world. But how do they stack-up against traditional airgun ammo? To find out, the HAM team made a test, shooting FX slugs and pellets in an FX Impact.
Using HAM’s laboratory-grade precision balance, we first measured the weights of the respective types of ammunition. The 22 Grain slugs actually weighed an average of 21.86 Grains. The 16 Grain pellets had an average of 15.86 Grains.
The air rifle used was a “Mark One” FX Impact, fitted with an original Smooth Twist barrel.
Our intention was to compare the velocity and kinetic energy of the FX slugs and pellets. They were shot under as near as possible to identical conditions. Same location, same equipment, same state of tune on the Impact, reasonably consistent wind. All shots were taken within a total of about 20 minutes.
For the test, we set a target 50 Yards downrange. We also set-up a Labradar doppler radar unit to record the velocities. This enabled us to record the Muzzle Velocities, together with downrange velocities at 10 yards, 20 Yards, 30 Yards, 40 Yards and 50 yards.
Ten pellets were fired and the resulting velocities averaged. The same procedure was followed for the slugs.
So what did we find?
FX Slugs And Pellets – Velocities
The slugs – being heavier – had a lower Muzzle Velocity than the pellets. The average was 860.5 FPS. But their 50 Yard velocity was higher at 772.5 FPS, due to their higher Ballistic Coefficient.
Here’s the pellet velocities. The more rapid decline in velocity with range is clear, due to their lower Ballistic Coefficient.
And here’s the two sets of velocities combined in one chart. Now we can see that the velocities are the same for both FX slugs and pellets at about 36 Yards.
FX Slugs And Pellets – Energies
Of course velocities are one thing. For hunting, the amount of energy being conveyed downrange is much more important. This graph shows how the slugs start out with a Muzzle Energy of 35.95 Ft/Lbs. This declines to 28.97 Ft/Lbs at 50 Yards.
The pellets had a Muzzle Energy of 31.30 Ft/Lbs, declining to 19.66 Ft/Lbs at 50 Yards.
The combined chart shows that the 22 Grain Hybrid Slugs actually have more kinetic energy at 50 Yards than the 16 Grain pellets do at 10 Yards.
Also we see that the slugs loose energy downrange much slower than the pellets. (The gap between the red and green lines increases with increasing range). That’s when fired from the same air rifle with the same tune settings!
You can find these results discussed in much more detail, together with BC calculations, in this subsequent post.