Every barrel of every gun is different, this max OAL number, while pertinant to a barrel it is known to work in, isnt really what you need to know. Yours most likely will be different. Our Handis dont have the mag dimention to worry about. So thats one less head ache.
You need to get your chamber dimentions, from YOUR barrel. More improtantly, the amount of leade or throat legnth. Try differend legnths until you find what your barrel prefers. A longer throat will allow you to seat a bullet farther out. While a short throat will not. But you can still acheive the same distance off the lands reguardless. This is the more important dimention.
Good Luck,
CW