If you have a prairie dog problem, look no further.
Prairie dogs are a nuisance, and landowners and ranchers are more than happy to allow people to get some target practice on ground squirrels digging burrows on their property. As such, they've probably been shot with, well, everything.
A couple years ago, I used a Wyoming antelope hunt as an opportunity to test out some new bolt-action rifles, all of which were chambered in 6.5 Creedmoor. Nearly all of us tagged out on the first day with plenty of time to spare, so the gentleman running the trip and the local outfitters made a journey to Walmart (it was the only place open) and bought them out of 6.5 Creedmoor ammo to go with what he'd already brought for us. So, our speed goat hunt quickly became a prairie dog hunt.
Now, a 6.5 Creedmoor is definitely overkill for prairie dog shooting, but we were pushing things, shooting from beyond 500 yards without sticks or bipods into some pretty serious crosswinds. While a 6.5 Creedmoor wasn't that absurd for this kind of shooting, it was still a bit much.
Inside 100 Yards
Typically, folks will be shooting at ground squirrels at much closer distances. When you stumble upon a populous prairie dog town, high volume is the name of the game. A semi-auto rimfire rifle chambered for .17 HMR or even a .22 LR can do a serious number on the population and make for a great varmint rifle.
Another great choice for a lightweight, accurate varmint rifle is the Savage Minimalist bolt gun in .17 HMR topped with a high-quality optic.
For medium-range shots, it's hard to beat a .223 Remington, and there isn't a better rifle for that cartridge than an AR-15. An AR doesn't need any special accessories or features to be a good prairie dog gun, as decent irons or a scope will get the job done. The .223 was originally marketed as a varmint round, largely because they can handle prairie dogs out to 450 yards with the proper optics, or good irons and really good eyes. With standard 30-round mags, you can wipe out a whole lot of prairie dogs in short order.
For long-range shooting, you will be taking slower shots at dogs, so anything from a basic Remington 700 rifle to a sniper rifle will do the job, as long as it's zeroed in and the shooter is steady. A flat-shooting chambering certainly makes things easier at longer ranges, as prairie dogs tend to inhabit wide open spaces with a lot of wind.
A few accessories are also helpful, like a rangefinder, shooting sticks, a bipod for prone shooting, and even a spotter doesn't hurt. Here's a secret: prairie dogs are pretty dumb. You can miss them with long shots to the right by an inch and again to the left, and they often won't even duck back into their burrows. So a spotter who can mark the dust from your hits is actually helpful.
If there's any feature a good varmint hunting gun should have, it's is a nice trigger. While you don't need a high-caliber bullet to do the job, you are shooting at small targets and you want to be as precise as possible. A good trigger makes for a steadier shot.