The firearm support device includes one or more “beanbags” directly mounted to a rifle stock that can be moved between a secured transportation position held against the stock and a support position suspended beneath the stock. The support device includes a stock attachment and one or more beanbags pivotally connected to the stock attachment. The stock attachment includes cinch and stirrup straps that secure the support devices to the stock and prevent it from inadvertently sliding up the stock. The bean bags are constructed of cloth pouches filled with a granular substance. The beanbags are sewn directly to the cinch strap or connected to the cinch strap by a slide buckle that rides along a rail strap sewn to a beanbag. The beanbags are securely held against the sides of the rifle stock in the transportation position by elastic cords, buckles, snaps, hook and loop fastening patches or other connection mechanisms.