Aha! I have finally figured out a way not to decide. I go back and forth about whether I want a 45 caliber rifle that shoots 2000, 2200, or 2400 fps. The Winchester Magnum is enough gun, but the aesthetics of a 500 grain bullet at 2150 or better are why I want a Lott at least. Kind of like picking a non-belted, rimmed cartridge for a double rifle. The buffalo will never know. It's just part of the whole picture. Now I have another part.

A 500 grain bullet at 2400 fps is maybe better. If some day the Lott has knocked enough sense out of me, and I decided I want to go up to a 460 G&A or 450 Vincent Long, if I'm not mistaken, I can take a Vincent or G&A reamer to that Lott chamber, and the reamer ought to clean up the belt and everything. I am in the middle of moving and don't have dimensions in front of me, but I know the Jeffrey case head is a couple thousandths bigger than the belt on the Lott case.

Am I wrong?

H. C.

Nope, it depends on the dimensions of
1) the chamber of your Lott up to the belt cuts and
2) the type of 404 brass you use as there differences in different makes of brass.
I went through something similar a little while when converting an extra 375 H&H to 375 Ultra.

I would be very cautious about trying to convert a Lott to a 460 G&A. The dimensional differences at the belt are not great and remember that to do this, the reamer will be basically unsupported until the pilot fully enters the throat. The result usually is lots of wobble/ chatter and total loss of concentricity.You need a real life machinist to do this without winding up with a EGG shaped chamber still containing the vestiges of your old belt. Few "gunsmiths" are going to have the gear necessary to do this right! I'd suggest you just buy a new barrel.
You might also just consider a long throated 458 win mag. Load the bullets out to 3.450 and fill with 81 grs of ww748. In a 24 inch barrel you may well see 2200fps.