I have loaded both Cast and Jacketed 300 gr. bullets for my Marlin .444, both are maximum loads. Which do you consider better for bear defense? Thanks-Karl

it all depends on how hard the lead is. I use wheel weight lead which is verry hard, have some 405gr cast round nose for my 45/70 that i have put through 34in of white pine and never found the bullet. I shot a deer with above combo and put a 45cal hole in and a 45cal hole out,it required a 350gr hp to finish the job(what a mess). as far as bear it depends on what you mean by defense, a hard cast will will penetrate from it's head to it's ass in a charge where a hp will expand to the size of a 50 cent piece and knock it over backwards. the choice is yours good luck

What type of bear? For a Black Bear, probably either would work well. For a Grizzly Bear, if I had to use my 45-70, I'd at least have a 400 gr. bullet, probably one of my hand cast RCBS bullets that has a good sized flat on the nose. They give more "smack" that a round nosed bullet and penetrate just as well.
I believe RCBS has an Elmer Keith style gas checked 300 gr. bullet that should work well. Anyway, that's the bullet I'd try if it worked well in my rifle.
Paul B.