I am looking for reduced loads for my 458lott I wish to use 405gr remington projectiles could anyone supply loads. just a note I can not get IMR powders here in Australia any help would be great
Ozishooter

In 45/70 with 405 gr cast bullets, I have found that most powders work.

Unique works great.
IMR4895 works great.

And there are allot of powders in between.

True optimum is somewhere around Re7, but it doesn't need optimum.

its easy.

take a safe load, for a 500gr, with quickish powder, and work from there

ozshooter, not sure how low you want to go. I have a 458WM, NOT a Lott.

I've been down to 405Rem. 41gr.2205 and 60gr.2207. Experenced excessive soot back to the lugs, hangfires, and lousy accuracy.
Not to mention a vast difference in POA to full loads.

Have you seen the ADI loads for 458WM? They show a starting load of 61gr.2207; 68.5 for 2219; 70gr.for BM2; and 72gr. for 2206.

My suggestion is for you to start with something like that and WORK DOWN, as jeffeosso says, looking for accuracy and your comfort level. With the quicker powders you shouldn't get detonation problems or need fillers, and the soot will let you know when the case isn't expanding in the chamber.