Has anyone got any load data for the 450 watts. I live in Africa so have limited access to brass and bullets. I have some brass that has been trimmed down to 69mm. I believe case length should be 72mm. The problem I have is that when loading 500gr mono's it compresses the powder. The only powder available to me is Somchems range of powders.

.458 Lott starter loads and a chronograph would be where I would begin. You'll end up with something very similar to the .458 Lott numbers. Look for Somchems loadings for the .458 Lott.

This is a first step:

http://www.bigbore.org/index.p...d=10&id=555&Itemid=0

Thanks for that, I've got a bunch of data for 458 lott, but my problem is that the only brass i have been able to get has been trimmed about 3mm shorter than the proper case length. So I am struggling with space in the case when useing S335 powder, even S321 compresses slightly

It's your lucky day:

http://www.gsgroup.co.za/loaddata1.html

It's .458 Lott data, and only for a specific make of bullet, but it's probably the best info that you'll get. Can you chronograph your loads, or are you using book estimates? With a chronograph you can simply start at warm .458 WinMag loads and inch upward until you hit your comfort zone. With no chromo, I'd begin with starter .458 Lott loads and move up to mid-range loads, if all seemed well. With a limited powder and bullet selection, there aren't too many variables to consider. If you can break 2100 fps with your 500 grain monos at a safe pressure, you've got something better than most of the nitro express loads of the past; most of the .458 WinMag loads as well.

May I ask a question?
Is there a problem using a compressed load with that powder you're using?
I only know of one powder that behaves badly when heavily compresse
d, but it wouldn't be suitable in a big bore anyway.
The 3mm difference in case length shouldn't really make that much of a difference, crimp at the bottom of the driving band/cannelure to give yourself more room if needed.
I load for a Lott, and quite a few of my loads are running compressed, especially with mono solids, haven't had any problems doing this yet.

Cheers.

Where do you live? You can source unformed cylindrical brass from PMP, You just have to size and trim to length. I have actually got some if you are interested.