I can see groups on steel at 550 through my Leopold mk4. I fully expect to see holes through paper at that distance through the ATACR, if not at least with shoot n see targets.
We leave our steel out, and im too lazy to go toss a coat of paint on it to see where I hit If I hear it, thats all that matters to me. I shoot for kill shots, not worried about groups unless im zeroing or testing to see which ammo works best. I will have to someday for fun, but the last time I used the 338 Lapua, it blew most of the paint off when it smacked the steel anyway.