Gene: I don't quite understand your point. You would like to use some 300 gn Beartooth Bullets but you don't have the time to work up a load for them(?).
But friend, if you are willing to put your butt on the line with someone's 245 gn 'store-boughts', or a 300 gn jacketed slug out of a factory box, I'm thinkin' you should get yourself a supply of the Beartooth hard-cast 300 flat nosed slugs delivered overnight. If you can work up one 300 gn slug load, you should be able to work up a load with the right 300 gn slug. Those piggies do not take lightly to being shot and they are and can be very mean and if you choose the wrong slug and it doesn't work you will be the one winding up on the dinner table.
Good luck, and let us know..... Mikey.