If your gun is lapped my 300 grain LFN with .45 nose and gas checks will make you real happy In most lapped Rugers it will print most shots into an inch at 100 yards if the shooter can point the gun EXACTLY the same every time and nudge the trigger carefully.
This bullet will come out the tube at 1450-1500 fps, so you'll quickly notice some recoil.
A 320 gr will be very slightly more accurate, but bogs down a bit in Blackhawks and S&W's, so it doesn't kill as well, and it has to be driven at max pressure for stability. If you had a Redhawk, or other long cilinder gun which would take the .5 nose length, the 320 grain would be my reccomendation. This one, with half inch nose developes speeds a good 100 fps faster than the 300 gr with .45 nose. One could safely say there will be recoil.
And, I mentioned recoil because you want to shoot a lot, which is wisdom, but recoil will be tiring.
PROPERLY INSTALLED gas checks always tighten accuracy compared to plain base, and especially so with heavy loads. By properly installed I mean done so the checks are squared during sizing, which I've explained several times on this forum
You'll find a very interesting thing happen in your learning curve with these bullets. They are so accurate that they actually teach you to hold the gun and release the trigger properly, because you'll see the bullet hit exactly where the sights are every time, and realize your error when the bullets don't land where you intended. - If a gun isn't precision accuate it's anybodys guess whether the gun or the shooter threw the shot, but when it 'drives tacks', all doubts are removed and it becomes a powerful teacher!