As far as I can see the small fuzzy mammal known as the groundhog. I have a BC in 45-70 and in 45-120. One has a Smith Enterprise ladder sight, the other has a Williams FP with the target knobs.
My uncle and I will take our big bore guns out to hill tops and walk shots in on chucks in the valleys and on the next hill side. Anywhere from point blank shots to at least 900yrds, maybe more(range finder doesn't go that far). My uncle uses a damn nice Browning Hi-Wall with upper level #2 loads. I use mid level #2's to low level #3's in mine pushing some modified 300gr JHP's(bored out to 250-260gr then a hot glue spitzer put in the cavity to bring the ballistic coefficient up). My farthest .458" chuck kill was about 550yrds +/-, my uncle's is about the same.