Finaly somthing i know tones about PD are the same as gophers (i think) Ive been using a .22 for years now with open sights Ive take a few out at 100 yards (B.S. luck shots) my father uses a stock ruger 10'/22 witah 4x tassco 22 mag scope I have used this gun and have taken gopher out to 60 yards (havnt seen any further) but i wish i had a bit more scope. I recently purchased a marlin 917vs 17HMR and mounted a simmons 4-12x40AO scope on it. its of plenty scope for shootin gophers out to 150 yards. the 17hmr is a fun little cartridge because its VERY explosive on small game. It has been known to blow gophers in 2 if there smaller and the bullet hits right but it does get costly at $11.99CND for 50 Rounds. Now how to hunt them i walk the fields manily there uslay preatty stupid unless they have been hunted hard. If they just have there head sticking out of the hole you can just stand still and they will come out. you can make a whistle by just holding an empty .22 shell to you bottom lip and blow it makes a high pitch squeal this will often cause them to come out of thier hole farther. If you can drive out into the field you can get even closer to them. just drive with your windows down and use your mirrors as rests. (shooting from vechical is illegal but on private property varmint hunting its no big deal around here any ways) a set of binos are a scope is nice to have to identify your target better. I hope this Helps.