I made that recommendation of 300 gr WFN 45 bullet at 1200 fps because it is a proven load that takes game to moose and big bears down quick. And because I have the belief that one should shoot a handgun that he can handle with precision, rather than get carried away with power that isn't needed and cannot be handled well by most handgunners, who are mostly confined to maybe 100 yard shots maximum at game. (Though this load will kill well at much longer ranges than that.)
Since you have the 454 and want to have the capability of shooting at long ranges, I'm going to assume you don't mind the heavy recoil. Choose either a 320 or 340 gr LFN and drive it at a speed that delivers the maximum optimum DV of 135. This using your chronograph speeds taken at short range. It will work very well out to at least 600 yards if you can hit reliably, which no one can with a revolver. But if you do punch a hole in the wrong place at a reasonable range and the critter is running, lay a line of lead for him to run through at any range until you punch another hole or three someplace. Even if the load isn't adaquate at long range. That's an Elmer Kieth concept in Smith words, because I subcribe to it.
Some load the 340 LFN in FA 454's to speeds as high as 1700 fps, which is way over what I recommend, and they love the performance. I don't know if the Ruger is capable of standing a steady diet of such loads, but if you like power, I designed all the bullets for top accuracy and high power, or maybe better, maximum power. By maximum power, I mean power far beyond that possible with any other bullet designs. They work VERY well with stout loads, but I learned after thousands of kill reports by customers and I guess perhaps at least 300 personal kills that we don't have to be kicked backward into yesterday to kill animals, so came up with the DV formua so customers could build loads that worked yet are reasonably pleasant to shoot.
