Thanks for all the excellent replies. It would appear that the reports I've read about 2400 not being position sensitive are either based on limited data (pistol cases) or just another example of internet BS being spoken as fact.
What I like about any new experience is the learning process. The web has accelerated most any learning process with the caveat that you might take a step or two backwards due to bad info being shared as fact.
No, I'm not looking to start my own ballistics lab and experiment with things like 20mm powder. Although several years ago I was offered what appeared to be about a 10 lb keg of some old military power, which I politely refused. But curiosity got the both of us. So, we took a spoonful, set it on a log and touched a match to it. Nothing. Upon closer inspection I determined it to be calcium carbide for making acetylene.
My goal here is an accurate load out to 500 yds with a decrease in recoil. My BP load was 70 gr of Cartridge with a 540gr Postell out of a Paul Jones mold. It knocks the rams down with authority. And somewhere, I have a target shot at 300 yds with about a 2.5 inch 5 shot group. But the geezer factor at the club has made resetting targets a challenge so now we shoot swingers. I want to go down to a 457193 at 420gr, but still be able to reach the rams with a degree of accuracy and consistency.
pretty much any published smokeless powder recipe will satisfy your needs without any fillers.
Yes, and that was the point of my question. The Lyman loads for the cartridge all include the Dacron wad mentioned previously. But, as has been stated above by others, just how that wad, (wadding, filler, powder positioner) is placed is very important. So, if it could be eliminated safely, that would be my preference. Unfortunately, it seems that for every shooter that does not use wadding, there is another who warns against that practice, pretty much cancelling each other out. One of the pitfalls of the internet.
I did notice the Trail Boss when I was researching powders. I have to admit that I'm out of date on current offerings, having not done any smokeless reloading in close to 15 years due to other things taking precedent. I found the Trail Boss loading info interesting to say the least. Fill the case full and then start with 60% of that amount if I remember right. That certainly flies in the face of all the things I learned about loading smokeless powders 40 years ago. But that might be the solution.