Ah...you HAD to post that, didn't you, Al?
Now that makes what I have to say just that much harder...
...mine is shorter.
Really, I'm not short, per se (5'8" / 5'9"), but in fairly good shape (translation: I can **** in the jelly donut belly when I have to).
I'm using an older rifle strap that is more like 55" long. It hangs at the right level, too...go figure.
Take a look...this thread was about an alternative strap, but got into length questions:
viewtopic.php?p=188752#188752
We've also had discussions about the *magic number* for the length for anyone, but nothing good has come out - because it really does depend a LOT on things we never measure - like your torso length (hip to shoulder) and overall diagonal girth. Yeah, know those numbers off the top of your head?
Best case is to do two things:
1) ballpark the size by taking a cloth measuring tape (as opposed to a metal one, since it will have to bend) and measure a loop from your left hip up over your right shoulder and back to your left hip. That will get you within a few inches, but isn't a real scientific measurement. But gosh, it should be close.
2) try a strap of a known length, see if it fits for you. If making your own, start at the longest possible length, as you can always cut more off.
EDIT: P.S. REMEMBER that the strap has to have extra to come back up to your sternum (or thereabouts) to end at the buckle. Sorry, forgot to mention that part.
Good luck and let us know what you figure out -
J