Wanting a bipod for a heavy long range gun. Have several Harris's and like them but want a shorter (either 6"-9" or 9"-13"), swivel type. I'm seeing comments about "pod locks", can someone elighten me on them and also the notched leg types? Sounds like what I'd like to try, but can't find them on Harris's site. Part #'s or suggestions appreciated, or a sponsor that sells them!!