All of my shots that I have been successful on have been within 50-60 yds, but feel the effective range is probably a bit farther than that, depending on the abilities of the shooter and the rifle. BUT, the 1000+ fps air rifles out there today, especially in .22 are pretty dern cool. Groundhogs tend to leave their burrows during the first two to three hours of daylight, and the last several hours leading up to dusk. Put in a .22 short even better. That’s where they are most commonly found. The gun I will be using is a mossberg/cbc .22 LR. put a .22 lr in a .22 mag chamber and POP, its done, and pretty quiet. It doesn't require hiking for miles to get to the best places. Consider trapping options....that works a lot more around here and lets me spend time shooting rats. How to Find Groundhogs. ps. I too have used a .22 for groundhogs in the past, and feel it is capable of taking them cleanly. As mentioned, the best way to find groundhogs is to look for holes in and around man-made structures. ST My .22 is semi-automatic. You can usually drive right up to the area and even hunt out of your truck if you so desire, while sipping on a cup of hot coffee. Thanks,nc.hunter. Most of my shots would be between 15-30 yards, although my gun is accurate to about 50 yards. Groundhogs are easy to hunt from one fixed, and comfortable position. What in your oppinions would be the best ammo for groundhog hunting? I have a box of cci stingers, how would they do on some groundhog at 15-30 yards?