I went the range a few weeks back and saw a guy that had some cool blue jean gun rest bags. He said they were filled with sand. I thought it was cool and decided to try my hand at it. So i took some old blue jeans and cut off a 13" section of leg and sewed it up by hand on both ends, leaving a 2" opening to fill it. It ended up being about 12" x 10" x 4". I also made up a small one 11" x 5". I filled my bags with rice I bought at Walmart in a big bulk bag. They are nice and heavy (not as heavy as the sand ones) and are just pliable enough to form a grove to rest the gun in and have improved my shooting exponentially. Didn't cost much money, only a little time. And I made some supper with the the leftovers.