I've got three .17 Ackley Hornet barrels for TCR-87 rifles and think a .17 Hornet is a caliber a varmint hunter should not be without. I've shot several coyotes with mine and one was just over 200 yards as was the one fox I got with them. I also have gotten more than a dozen raccoons and three bobcats. My last .17 Hornet barrel is 18-1/2 inches and has a suppressor on it. The short length only lost less than 100 fps and is much quieter than I expected as the cartridge uses so little powder and the sonic crack of a .17 caliber bullet is much less than that of a .22 caliber bullet. Also, I have a nice Anschutz rifle in .17 HMR but haven't used it since I got my first .17 Hornet barrel. A .17 Hornet sighted in to hit a little less than 1-inch high at 100 yards hits less than 1-inch low at 200 yards. I've only shot one groundhog withit as they are not too numerous where I live. It was a couple feet in front of wooden steps of a friend's rental house and there was no exit hole to bloody up the steps or bullet fragments to damage them. Fiinally, with the much higher velocity of the Hornet compared to the HMR, there is significantly less wind drift.