Which one develops the most velocity and what are the advantages and disadvantages if any between the three cartridges for hunting later on in say Africa.
All of them will drive a 500 gr bullet 2300 fps and change, I seriously doubt there is so much as 50 fps between them all, the cases are very similar in capacity.
My personal preference is the lott, as it is a factory round, kinda sorta. I'd also add the Lott and Watts will feed, chamber and shoot 458 win mag ammo with no loss in performance. The ackley will fire win mag loads, but the case blowing out will drop velocity. You could get a Lott and have the watts chamber cut, if you just had to have the extra .050" case capacity. Now that Hornady offerst belted basic brass, they are all easily formed. A-square made ackley brass, so properly headstamped brass is available, though of dubious quality. Hornady offers factory loaded 45 lott ammo.
While I don't think the 458 lott is the ideal 45 round, it is the most practicle. It achieves 500 gr @ 2300 fps, will shoot the relatively common 458 win mag in a pinch, and is a factory loaded round. It is also small enough in dia to offer 4 round magazenes w/o too much grief or expense. Wonder when my replacement one is arriving?
Steve