404 I was using 8x68S for some time before I got infected by 9,3's. I was using ABC bullets (X-type) and those worked great. As you have found out this caliber is a bullet breaker "par excellence". Among others I have used factory loaded 224 Cone Points. While extremely accurate there were some spectacular failures:

- roe doe (15kg) shot broadside, entry behind the shoulder exit on the front of the throat...
- red stag shot steep downward, entry high on the shoulder, exit should be very low on the opposite shoulder but was just under the spine on the mid ribs...

Cone Ponts were much better from beginning - Nickel plated steel jacket, modern ones are copper jacketed and far too soft IMO.

In 8x68s speed frame I'd pick 200gr A-frame - tho pricey it might just be the ticket, not to mention Woodleigh's Hydro - now that is the kind of bullet concept that would be just plain perfect for 3000fps with IMO spectacular results - sadly as far as I know those are not available in .323?