I shoot out in a rural area. We have a great back stop and I have the range to myself whenever I want to shoot by myself or take a friend.......
I have a 3 legged shooting bench that is very steady and stable . It works well. I'm 6' 5" , so my chair height to the table and the height needed for someone that is 5' 6" is quite different. We continue to have problems with chair height.
My friends and I have a folding chair that has worked about as well as a submarine with screen doors addressing this height problem.
I finally decided to make a shooting stool that is adjustable for height. You can make height changes in 30 seconds. I think this will solve our problems. The adjustment is made by moving a pair of 5/16 " dia. bolts that have wing nuts on their ends. Quick, low tech, and safe. Every where two pieces of wood touch there is wood glue. This one will last for a LONG TIME !
The first photo is of the bench ( this isn't our problem ).
The next photos are of the adjustable seat :