The millennium ladder stand I was hunting out of yesterday is 21' to the seat I think. It's got a rail around it but to shoot my bow I'd have to stand, it'd be real easy to slip & go over the rail while trying to twist into position for a shot. As I post this I'm sitting in a home made basket style stand chained to a tree, it's about 20' up. It would probably hold 1000 lbs but it's not an engineered & tested product, it was built by a couple of guys in their backyard with a welder. I trust it, but not enough to not wear the harness.
A fellow I went to high school with fell from a stand when he was 21 and spent the next 22 years paralyzed below his chest until he decided life wasn't worth living any more. Two years ago he stuck a pistol in his mouth & ended it. Not ideal under any circumstances.
