The answer is the 17 Ackley Hornet. I kill them at 25 yds, no exit, I kill them at 250 yds no exit. I love the Browning 22 Hornet, so I bought a second one and wildcatted it to the 17 Ackley Hornet. Now they are marketing a Hornady 17 Hornet which is close, couple hundred fps short of my Ackley Hornet. Accuracy is everything, don't rake em'
At 3900-4000fps, the little 20 grain bullet disintegrates and the hydroshock inflates them, you can see it through the scope, they swell up then they deflate and drop. I sometimes find copper metal "flakes" in the outbound side inside the hide but not all the way through.
My 17 Ackley Hornet has killed a bunch of foxes, both Reds and Grays, not a couple here and there. I love its performance. I have tried them all.