Keith is right, the 22 Hornet is way overkill for only 75 yard shots on ground squirrels IMO too. I currently have pistol length barrels in 17M2, 17HMR, 17 Ackley Hornet, 17M4, 17DT, 17 Rem, 22LRM, 22WMR, 22 Hornet, 218 Bee, 221 Fireball, 222, 223...(and 6/6.5 wildcats) that I have hunted a bunch of ground diggers with over the years. If you are only going to be shooting 75 yards, any of them will get the job done easily on GS's... even the rimfires. Guess it depends on how high you want to toss them, and in how many pieces. What really shines in the digger fields and a bunch further than 75 yards is both the 17 rimfires, and if you want to reload center fires the 17 Ackley Hornet. They are all perfect small critter getter's. At the annual 10-day Belding shoot I host for friends we get very long days of almost constant shooting. Our "gentleman's agreement" is no shots under 150 yards. That's stretching the 17M2 some (although it will kill cleanly with a good hit). But the 17HMR is perfect for these little diggers on shots up to a bunch further out than 150 yards.
Up to 100-125 yards my first choice would be the cheap to shoot 17M2 with plenty of quality glass on it.