What Powder

[alfajim]

No crimp is the best way to go with accuracy. A tight slip fit will serve much better.
Drilling out the flash holes is a pretty good way to wreck a bunch of cases.

A little off subject maybe but now that all the brands of cases are avalable which brand is best to get the 70grs in with the wad and how much compression would that require especially with the .500gr bullet? Figure I best pick some up now before they all disappear.
Also would it be a good idea to make the wad a grease wad with paper each side to keep fouling soft?

Jim