Sitting positions will usually be determined by your body configuration and the terrain.
When I was younger I could get down and place my elbows inside of my knees but as I got stiffer with age I went to the open leg position. I live in the NC mountains which abound with steep hillsides and find that the open leg position, even though it may not be the most ideal sitting position allows me to adjust to the hillside and is easier to maintain.
Just try the three positions and decide which is the most stable and fits your situation. Target shooting may use one position while hunting may require another. Practice with both.
I usually use a bipod from the prone position while shooting sticks are use for other positions. The use of a loop sling should also be considered as it will really help your shooting.
montveil in the NC mountains
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