I would say your about right with the 22-25 inch measurement for most mature mulies. I think the main thing you need to know is your gun's performance. If your comfortable with your gun and know its capabilities, you'll know what kind of shots you can take on a responsible level. The other thing is knowing your distances,(rangefinder), to know what shots are possible. So say it is 24", I would say that 12 of the 24 inches is a kill zone to put that muley to sleep from high shoulder to vitals. Know your gun and you'll know your limits.