Curious to know if anyone on the site has used the Jae-Bok Young .458 Crater or Crater Jr on PG or DG or US BG and to what success or failure? If so, anyone willing to share first hand reports?
http://www.competitor-pistol.com/jb%20bullets.html

From all reports they are very good...but hard to get...long waiting period, 2-3 mo last time I tried...I won't wait that long...the same for Beartooth 525's, but that was last winter when I tried the last time. Anything over about 430 gr are hard to get seems like.

Ranger Rick has some 1.68" long, 720 gr, .458's Tyrannosaurus Thumpers that are awesome and shoot extremely well in my 45-120...and that 4.5" cartridge will make your eyes pop in your hand or out the muzzle. Hahahahahaha

You can find some softer cast, low velocity, 500 plus gr, BP slugs in several places including Midway. The ones I've shot at pine logs, slicked up with additional lub work OK up to around 2000 fs and do a very good job in penetration. They do rivet in the logs at the higher velo...lodgepole pine logs are a tough test for bullet and so is my sand box. I got almost 3' of penetration with the 720 gr slugs...nice way to split wood, doncha think???

You just have to buy some and try some in your shooter at your velo to know for sure. The levergun guys seem to like them.

I haven't taken any game with any of those bullets yet, but wouldn't hesitate on anything except African DG. If my 54 cal BP rifle will knock down bull Elk and moose with a relatively soft round ball, the hard cast lead slugs will do just as well.

I'm looking forward to trying some of RR .512", 745 gr and 975 gr slugs in my almost built 50 Rigby.