Decided to upload some pictures of a target stand I came up with a year or two ago. It's made from pre cut Lowes rebar and turnbuckles. It completely breaks down and will fit in a tiny trunk. Thus far it has taken hundreds of rounds of 300 win mag as close as 200 without issue on hard and soft surfaces. It has only minor wear from shrapnel as well.

Assembly starts with the third picture. As long as you have the turnbuckles and rebar like this it will be very stable with all the tension holding up the top bar.