If you are hunting or looking for maximum defense,,,,
then you need to probably look at jacketed, and in my opinion, at least 250 gr Hollow points. I say this so that you can get the most out of the caliber (which by the way I'm partial to !!).
Once upon a time I would have fully agreed with your statement, but as of a few years ago and especially after last year, well I might say your barking up the wrong tree.
Not saying that one cannot get good performance from jacketed bullets, but to say they are necessary for top end performance in hunting or self defense is simply being a bit closed minded, or ill informed.
Cast bullets were the staple for a good hundred or more years before jacketed became the rage. No reason why they still cannot be counted on. I can also attest to the fact that on three different occasions a standard loaded 45 Colt 250'ish grain SWC did a fine job of putting all three BG on the ground in front of my grandpa's gas station when they tried to rob him. Even with no expansion either the 44 or 45 will make a goodly sized hole through what ever they are put to task on.
With what limited testing I have done with cast in RFN, SWC, and HP's I have no reason what so ever not to trust them just as much if not more to do the job I need done when the pressure is on.
The following are only a couple of post I have been apart of, and I know there are hundreds more tests being preformed all the time by serious casters. Be sure to look at the link to "Alloy Testing" right after the pictures as well.
Pouring HP's and Learning to Blend Alloy's
In this test I actually put up a couple of the most recommended factory JHP ammo against my own cast HP, You tell me which one you would rely on, and why.
Cast - VS - Jacketed
I realize that this was a simple test and I make that statement. I know for a fact that the others will indeed expand and will put the brakes on most any BG if the need arose. I also have to believe that my own would also pretty well change any intentions of ill will coming my way.
What I have also found has been that using the proper alloy that both the SWC and the RFN designed bullets I get plenty of expansion as well. Then there is the argument that I cannot drive the cast as hard as I could the jacketed, BULL, I've run some cast loads up to 1700fps from my 454 gas checked, up to mid 1300's in both my 44 and 41 magnums flat based no GC, and up to over 1200fps from my 45 Colt same as the magnums no GC. Trust me when I say they wiiilllll GIT-R-DUN.
The key with cast is fit, and then lube. I am simply tumble lubing mine with a variation of the Lee Alox. It works so why change it.