For reference, I could tell you where to find a bait shop with a picture of a 17ft from Lake Monroe. Two hunters laid next to it, head to toe + head to toe and the gator was still bigger! State wildlife officer did not measure so it's "unofficial", but the pic is proof enough for me!
I use the Landry CCI .22 WMR Maxi Mag in my Brandes .22 WMR AR upper. Really nice unit; consistently accurate giving 5 round strings at 50 yards (from sand bags) well under 0.5 inch, (some in the 0.3” range).