The Sub16 comparison.

No. Too complicated to get rabbits to stand sill at such specific distances.
I’ve taken a more practical and more “commonly encounter by hunters” approach.

Ive got the 3 rifles set up as follows .177 15.9FPE, .22 15.6FPE and .25 15.9FPE at the muzzle.
To get 3 rifles set up with their preferred pellet, and tuned to be accurate, while all being with in 0.3FPE of each other is a feat in its self.

I’m then going to try and document, recover and autopsy 3 head shots and 3 chest shots with each caliber.
Planning to try get one head shot and one chest shot with each caliber at 30ish, 40ish and 50ish yards, then comlpair how many FPE each had at the actual distance the shot ended up being taken (according to a reputable balistic calculator) and what its terminal performance was.

Pauly, Ja, in my experience .177, even in lower FPE, ice pick their way through a rabbits head even at longer distances. I guess it comes down to resistance, pressure per square mm???
Like compairing pushing a needle through a potato (.177), compacted to a knitting needle (.22), compaired to trying to push your finger through a potato (.25). U can apply the same amount of force to all 3 (sub16FPE) but some will pass through easier and others are going to deliver more energy and require more energy to pass through.
I was quite surprised to recover those pellets from the brains, I wasn’t sure what the .25cal would do, was half expecting them to pass through, pleasantly surprised that they didn’t!

Myson, interesting video. I have seen it a long time ago, but from bow hunting experiance and also from shooting big heavy charge stopping caliber rifles with 500 or 550gr monolothic bullets, I know that heavier projectiles might start of a bit slower, but the further they go the better their performance gets (compared to lighter weight projectiles) they lose less speed and hit harder at the target.

My hunting arrows are 750gr!!! Comparatively slow, but they have so much inertia, they stop for nothing and go stright through everything 😂😂😂

To translate that into what I’m compairing with these 3 calibers, they all leave the mussel with just under 16FPE, the .177 is doing 920 fps, the .25 is doing 519fps, but at 100y the .177 is down to 4.2FPE, and the .25 still has 7.8FPE . Not quite double, but close enough 😳

Yea, it'd be interesting to see the different calibres delivering the same energy, and the result.
So is it possible that if you had taken the same shot with a .177, would it have passed through?