I wonder how it is that you're sitting while shooting. Are you crossing your legs in front of you or have them wider than your shoulders, knees bent and out in front of and to either side of the shooting sticks? Are you simply letting the gun sit on the sticks, or are you holding the x of the sticks under the rifle or ? Where are you placing the sticks on the stock, near the sling stud or back closer to the trigger gaurd?
With my shooting sticks, I can sit and shoot prairie dogs out to 200 yards on a regular basis. Finding your comforatable postion is key, and using them many times will help. I'll never use a bi-pod that is attached to my calling rifle again!