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EDIT: Oops! I forgot to change the barrel from 24" to 20". I will correct and re-edit shortly.
Hmmm. Well, I just also noticed the cannelure in Hornady's photo of the 300-grain bullet looks like it is about 1.33 calibers above the base, so I didn't have it seated deeply enough on my 24" barrel pass. With that loss of powder space and shortening the barrel to 20", the MV is about 2000 fps, with 1000 ft-lbs retained to 482 yards. But this slow bullet drops like a stone. With a 1½" tall scope centerline, the PB sight-in range is 140 yards for a 4" circle (Jeff Cooper's criterion to allow for hold area to expand that circle to 8"), and it makes 162 yards the maximum PB range. At 200, you need to hold about 5 inches high. At 300 it is 2½ feet of hold-over. At 482 yards it is 10½ feet.
I also note that at 200 yards, a 10 mph cross-wind will move this almost ten inches, so the wind has to be watched. I would call this a 200-yard field chambering, after which longer shots could be made using a laser rangefinder to determine holdover and possibly a wind speed meter, but they wouldn't be quick shots.
EDIT: Oops! I forgot to change the barrel from 24" to 20". I will correct and re-edit shortly.
Hmmm. Well, I just also noticed the cannelure in Hornady's photo of the 300-grain bullet looks like it is about 1.33 calibers above the base, so I didn't have it seated deeply enough on my 24" barrel pass. With that loss of powder space and shortening the barrel to 20", the MV is about 2000 fps, with 1000 ft-lbs retained to 482 yards. But this slow bullet drops like a stone. With a 1½" tall scope centerline, the PB sight-in range is 140 yards for a 4" circle (Jeff Cooper's criterion to allow for hold area to expand that circle to 8"), and it makes 162 yards the maximum PB range. At 200, you need to hold about 5 inches high. At 300 it is 2½ feet of hold-over. At 482 yards it is 10½ feet.
I also note that at 200 yards, a 10 mph cross-wind will move this almost ten inches, so the wind has to be watched. I would call this a 200-yard field chambering, after which longer shots could be made using a laser rangefinder to determine holdover and possibly a wind speed meter, but they wouldn't be quick shots.