My blackhawk will routinely put my light OR my heavy load into an inch, which is about as good as my eyes work with iron sights, at 25 yards. My light load is a Lee mold, cast 255 flat nose over 8.3 grains of Unique. My heavy load is 18 grains of 2400 and a 300 grain Hornady XTP JHP. It's a hot load, but the Ruger handles it. I mostly shoot the light cast bullet load, of course, and the heavy load is for hunting and walking in bear woods. Since I haven't hunted with the gun much (usually grab my .30-30 Contender), it's rarely fired with the 300 grain load. Both Redhawk and Blackhawk are strong enough for this level of load. I just prefer the single actions for field use. The 255 grain load clocks a little over 900 fps and the 300 grainer clocks 1120, this from a 4 5/8" barrel. I really like the Blackhawk better for carry, lighter. I originally got the thing when I was chasing hogs at night with a guy who had dogs. It wasn't for taking the hog out, we cut their throats with a knife when the dogs had 'em pinned, but for just in case a big boar got loose of the dogs, which didn't happen. At the time, all I had were a .357 4" Ruger Security Six and a 1911 to carry. I wanted more and I love Blackhawks and I've always liked the idea of the .45 Colt in a Blackhawk. Well, now I'm a real lover of the combination having owned this gun for about 20 years. I no longer chase hogs, but I have hogs on my place and often carry this gun down there when I'm working on something or just bumming around.
For your uses, you'll probably want a a 5.5" or longer barrel. I LOVE the 4 5/8" Blackhawks for balance and carry, but a longer barrel will zip the heavy loads a lot better and give you a little more sight radius. I get 1200 fps out of my 7" .45 Colt/.410 Contender barrel with the same hot load. That's about 1000 ft lbs and bear in mine, that barrel loses quite a bit in the long jump of the bullet to the rifling where there's quite a bit of blow by. In a 7.5" Redhawk or Blackhawk barrel, that load would probably kick up 1250 or better.
Hope that experience helps you make up your mind. I have a single action bias, so don't let that bother your decision. LOL The Redhawk is a great gun, just a might heavy for my uses and doesn't have the lovely look of the single action. It does have the advantafe of a little faster lock time in single action mode. I see no real use for DA in a field gun, though, none at all. I probably have watched too many Clint Eastwood westerns, though. Joe Kidd was on last night.
