Bill, I can't tell you exactly what he had dialed in but he uses that standard equation. This is my buddy's rifle and he is quite an accomplished shooter, has his own particular loads, all his brass is fire formed to his rifle, keeps a strict round count on his Howa barrel and he has spent a lot
of time on this particular range. His dope is spot on and he can start at 100yds and take that rifle out to 1000yds without breaking a sweat but he's equally good at working out unknown distances with MilDot. No easy days in Oklahoma, though. There's almost always a stiff wind and on this range, at 400-600yds there is a confluence of wind directions owing to the terrain that can mess with even the most accomplished shooter's head which is why they were shooting at 300 yards. As you would probably agree, 300yds isn't all that far but it was much farther than the listed "safe" distance for that particular load of Tannerite so we were in very good shape.
I had a very good day the following day as and was making consistent 200yd hits, offhand with iron sights, with my 12 gauge using rifled slug at 1400+ FPS and sabot at 1600+ FPS in a helluva strong crosswind that was blowing ME around! Point of aim with sabot was roughly 18' to the right and about 10' above the target! That should give you some idea of the wind I was dealing with and frankly, I think that's pretty fair shooting. Train hard now and the shooting comes easy later on. Love my shotguns as much as I love my ARs. They're always a crowd-pleaser.
Anyway, we have a good, safe time when we're out there.
As for running the bolt home "like ya got a pair", my son had been dick-fingering the bolt and needed a little encouragement.