They shoot great so far. I've put around 450 give or take down range since i started casting. On Iron sights at 100 yards, i'm able to get a 12 - 13 inch grouping if i really push myself.
As for the charge differences, the lowest charge is 21 grains according to my reloading data manual for the 185 grain cast round. The highest charge is 28 grains (I believe, I would need to double check that as it may be 29 grains as the highest charge). I have been slowly upping the charge to experiment with it. 26 is the highest I'm comfortable with at this point.
I love to shoot the 21 grain charges because they are very light on the recoil. I can shoot them all day long. The 26 grain charges have a bit more kick, but nothing compared to the Winchester SuperX rounds. (The wife who is quite small hated the rifle because of the kick until I gave her the cast 21 grain rounds, now i have to fight her for it at the range!).
Yes they are gas checked and well lubed. I've had no signs of leading so far. After reading about casting your own boolits, i decided to give it a go. I was EXTREMELY paranoid about leading other issues so for the first 20 rounds or so I pulled the bolt out after ever shot to check the barrel for obstructions (just paranoia) and then relaxed that to every 10 rounds. I don't do that any more unless a round feels a little off (haven't had that happen yet, hope I never do). No signs of leading, the groves are in fantastic condition for the rifles age.
As for making 4000 rounds..... My good god! I have around 1000 rounds cast sitting in a box. I don't think i would have the patience to load all of those with my single stage press!!!!!
My only complaint is the crown at the top of each round caused by the bullet seating die. I wish I could get rid of that. But that is made up for with the smell of IMR 4227. I don't know why but it just smells like Alaskan King Crab and melted Garlic Butter to me. Best smelling powder I've ever had the pleasure of smelling after fired.
I need to check the regs, but I'm hoping to use the 26 grain rounds for hunting Coyotes.