RE: Will somebody fill me in on the Mini14/Mini30?
As for calibers: 10/22- .22lr
Mini-14 5.56mm(.223)
Mini-30 7.62x39mm
SKS 7.62x39mm
Any of these can certainly be used for varmints,some even use them for short range deer(the 7.62x39 that is,the others are to light).Their popularity could be put up for debate,but it's probably due to putting accurate firepower in a small package.There is an unlimited supply of acces. as well,so even though some of these cater more to the anarchist than the hunter,they maintain their status.