Choosing a caliber

IMO, 75 yards is stretching the humane, effective range of a standard power .22 air rifle. If you shoot a few groups at that range, I expect you might find that they are considerably larger than the lethal area of a squirrel. But, perhaps I am influenced by my own lousy shooting!
Are you talking with slugs?

I shoot 20.2 gr nsa

At 100y they still maintain 28fpe
At 200y 20fpe

Accuracy is an issue, for sure. But I hav no issue consistently hitting eggs at 100-120y
 
No, I shoot only pellets. And you're clearly the better shot!
5 shot at 152y
Shooting out of my truck window in 7mph breeze…group is inside 2”

Slugs really changed this game…this is no high power….just 20.2gr
600mm mk2 impact will do this on a 130bar reg

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