Furthest for me was 775 yards with a Rem 700 LSS in 300 RUMw/200g SMKs at 3200fps.
Spotted him across the canyon and he was mousing. I laid out the harris bipod, cranked the leupold up to 18x, dad ranged him at 775. I dialed to 775 and let her go. Right over the back my dad said, inches. Coyote looked up kinda stood around like whered that shot come from. I jacked another in real quick and this time held at the belly line and touched the 2 off. Bingo, coyote went down spinning for a while and eventually died.
I missed 2 with my 338 EDGE/300g SMKs at 950-1000 yards couple years ago. Each time I only got 1 shot off since that 300g went inches over there back, they got a nice dirt bath, so they never stuck around for me to get a 2nd shot on em.
I'm going to try again this year for a 1K dog with my 264 and 140g amaxs.