Energy Guide · FPE

How much FPE do you need? Airgun energy chart by quarry

By James · Updated September 24, 2026 · Editorial policy

Quick answer: For rabbits and squirrels, plan on 9–12+ FPE at the animal with a head shot. That usually means a rifle making ~15+ FPE at the muzzle. Rats, mice, and sparrows need less (6–12 FPE). Raccoon- and groundhog-sized animals need 20–40 FPE. Coyotes and hogs are 40+ FPE work for large-caliber and big-bore rifles. Placement matters more than any number on this page.
How this page was built

The quarry guidance below combines published recommendations (linked in Sources) with the energy floor I hunt by. The FPE-by-speed tables are computed with the same formula as my FPE calculator (grains × fps² ÷ 450,436, the AAFTA divisor), not measured. Your chronograph has the final say. Full methodology & editorial policy →

Airgun energy chart by quarry

QuarryPublished guideline (muzzle)My floor at the animalCaliber I'd useShot
Rats, mice, sparrows, starlings6–12 FPE6+ FPE.177 or .22Head
Tree & ground squirrels12–20 FPE9–12+ FPE.22Head
Cottontail rabbits12–20 FPE9–12+ FPE.22Head
Jackrabbits & hares12–20 FPE12+ FPE (20+ at the muzzle recommended).22 or .25Head, or heart-lung up close
Pigeons & Eurasian collared doves12–20 FPE12+ FPE.22Head or upper chest
Raccoons, groundhogs, opossums20–40 FPE25+ FPE.25 or largerHead
Coyotes, hogs, turkeys40–100 FPEBig-bore territory.30 and upCheck legality first

The guideline column follows Umarex's published FPE bands, which are muzzle-energy ranges. My column is what I want arriving at the animal, which is stricter because energy drops with distance. Mourning doves aren't on this chart for a reason: they're federally protected migratory birds and air rifles aren't a legal method for them.

FPE by pellet weight and speed

Look up your projectile weight and its chronographed speed. The number where they meet is your muzzle energy. Energy depends only on weight and speed. Caliber changes how the energy is delivered, not how much there is.

CaliberWeight600 fps700 fps800 fps900 fps1000 fps
.1778.44 gr6.79.212.015.218.7
.17710.34 gr8.311.214.718.623.0
.2214.35 gr11.515.620.425.831.9
.2215.89 gr12.717.322.628.635.3
.2218.13 gr14.519.725.832.640.2
.2225.39 gr20.327.636.145.756.4
.2525.39 gr20.327.636.145.756.4
.2533.95 gr27.136.948.261.175.4

Computed: FPE = grains × fps² ÷ 450,436. Weights are common real-world options (for example 8.44 gr .177, 15.89 and 18.13 gr .22, 33.95 gr .25).

How fast does a .22 need to go for 12 FPE?

This is the speed that has to arrive at the rabbit, not leave the muzzle, to deliver the floor energy:

.22 projectile weightSpeed needed for 12 FPESpeed needed for 20 FPE
14.35 gr614 fps792 fps
15.89 gr583 fps753 fps
18.13 gr546 fps705 fps
25.39 gr461 fps596 fps

Heavier pellets need less speed for the same energy. But they drop faster, which makes holdover discipline more important past 30 yards.

Muzzle energy vs energy at the animal

Every number printed on a box, and every number in the tables above, is muzzle energy. Pellets start shedding speed the moment they leave the barrel. How fast depends on the projectile's shape and ballistic coefficient. Slugs and heavy domed pellets hold speed better than light, flat-nosed ones. By 40–50 yards, a light pellet can have lost a meaningful share of its energy.

Three ways to stay honest:

  1. Chronograph at the muzzle, then run your ballistic coefficient through a ballistics app to estimate speed at 40–50 yards.
  2. Or chronograph at distance. Set the chrono up at 30–40 yards (safely!) and measure what actually arrives.
  3. Or build in cushion. This is why I say ~15+ FPE at the muzzle for a 12 FPE floor at typical rabbit ranges.

Why placement beats power

A .22 pellet in a rabbit's brain at 10 FPE kills cleanly. The same pellet in the gut at 40 FPE doesn't. Jim Chapman makes the same point in Afield on Airguns: accuracy first, power second. Extra energy buys you range, meaning the ability to still have enough energy at 60+ yards. It doesn't make normal shots deader. That's the core argument of my rabbit rifle tiers.

Run your own load in the FPE calculator →

FAQ

How many FPE does it take to kill a rabbit?

About 9–12+ FPE delivered to the rabbit's head. I use 12 FPE at the animal as my floor, which usually means a rifle making 15+ FPE at the muzzle so there's cushion left at field distances.

How many FPE do you need for squirrels?

The same 9–12+ FPE at the animal as rabbits, with a head shot. Squirrels are small but tough, and a body hit often means a squirrel lost in a tree or a burrow.

Is 12 FPE enough for hunting?

For rabbits, squirrels, and pest birds with head shots at sensible ranges, yes. It's the UK's legal limit for air rifles without a firearms certificate, and British hunters take huge numbers of rabbits at that power. It is not enough for raccoon-sized animals or coyotes.

How do you calculate airgun FPE?

FPE = projectile weight in grains × velocity in fps² ÷ 450,436. Example: an 18.13 gr pellet at 900 fps = 18.13 × 810,000 ÷ 450,436 = 32.6 FPE. Use your chronographed velocity, not the box number.

What FPE is a .22 air rifle?

It depends on the rifle and the pellet. Entry spring guns and small PCPs sit around 12–20 FPE, typical hunting PCPs 25–45 FPE, and high-power PCPs shooting heavy slugs go well past that. Chronograph your own rifle to know.

Is more FPE always better for hunting?

No. Past the energy that reliably kills your quarry, extra power buys range, not deader animals. It also costs you noise, air, shot count, and often accuracy. Pick the energy your quarry and distance need, then work on accuracy.

Sources

JS
Written by James · Southern California airgun hunter. Every recommendation on this site comes from animals actually taken in the field with my own gear — an FX Impact M4 running 40.1gr ACE FRAG slugs under a DNT Zulus 4K, with every hunt filmed through the scope. If I haven't hunted with it, I say so. How gear gets tested here →

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