For a Varmint rifle, you'l probbaly want a solid (non-collapsible) stock that is comfortable for you. A lot of my time varminting has been behind the stock waiting for something to shoot at, not actually shooting. If you're going to be laying there looking through the scope for an extended period, you'll want a stock that is the correct length, height, offers the correct cheek weld and eye relief FOR YOU. An A2 stock fits most people, an A1 fits others. The PRS mentioned above is fairly long to start with, but is adjustavble longer if necessary. It aslo has an adjustable cheek rise and a portion on the bottom of the stock for off hand support. The FX stock is also popular on varmint rifles due to the foam around the extension...it doesn't get too hot or too cold like some stocks can in the sun or wintery conditions.