Handgunr, check the Midsouth link above. They also have BlackMag3 but NOT cheap. No need to oversize, size them to exactly fit the sabot (.451 for a .451/.50 sabot) - I think that will give you optimum results. Oversizing will make loading EXTREMELY difficult.

Recommend you buy yourself a good quality range rod while you are Midsouth, something solid or at least unbreakable and with a good handle. Harvester makes a nice little short starter that works as a palm saver (check those at Midsouth).

You might also take a look at the nose of the bullets you are going to cast and try to find a seating jag that will do the least damage. Barnes makes an aligner that works well with most bullets but also tends to work loose on the rod. You might want to cruise around at http://www.cainsoutdoor.com/cart/asp/item_index.asp to see what they have in the way of rods and attachments. Super Rod Range or Hunter models are very good. I have one in 7/16" diameter that gets a lot of use (when I shoot [] ). Cains is a good place to stock up cleaning accessories while you are there.

Something else you are going to need is cleaning patches - start looking for buys on those or break out the old underwear and start cutting. Something close to 2" sizing should work nicely.

By the way - Triple7 is most definitely corrosive. Under certain conditions, it is only slightly less corrosive than Pyrodex. Pyro select is just a more expensive RS that supposedly is screened to a more consistant granular size. I like Pyro P - shoots cleaner, burns hotter, measures better, and more shots/pound.

Funny thing how "barrel ringing" that was always such a concern is never mentioned with Triple7 loads....