I haven't really load developed. I loaded up the 50 grain Mid South over 17 grains of RL 7 and I loaded them up into the lands. I have not even run them over a chronograph yet. I am estimating I am getting some where between 2800 - 2900 fps, but the proof is the chronograph. I was getting around 1" or a little under 5 shot groups at 100 yards with it. I wanted to get it ready for chuck season and I am running out of time. I also had to sight in a remounted scope. I just measured where the bullet had to be to touch the lands and then loaded up 50. I used them to sight in with. I have not really settled into a load really - just what I threw together. It might do better at 17.5 or at 16.5, just have not had a chance to try different loads out or it might do better off the lands. I do like RL 7 for the 221 Fireball. It seems to perform well in all of my Fireballs. IMR 4198 seems to do as well if not better than RL 7 as far as accuracy, but it will not get as high of velocity. 2900 fps is a pretty hot load with a 50 grain bullet using IMR 4198. I think it does slightly better with 50 grain V-Max bullets, but I do not feel that the Varmint Nightmares are much of a handicap.
BTW I do not make loads for my T/C heavy. I like to neck size only and If I load heavy I have to push back the shoulder a little each time. For my Remington 700 (26") and Stevens 200 (18"), I load a little warmer. I like 18 - 18.5 grains of RL 7 for those rifles.
