Here's a photo of nephew with a big cow elk in a cow hunt that allowed short range weapons only. The shot was 40 yds but he was accurate to 100yds during his practice sessions, I'm sure 125yds is not out of the question for a 12 gauge slug, it had a rifled barrel. I'll also add it dropped that cow in her tracks with a shot just behind the shoulder as you can see if you look for it!

ElkNut1