I've played with them. Home cast BBWC in my case.

I figured that they had more surface area against the lands and grooves, so I worked up to the equivalent magnum load for their actual weight and cut it off somewhere in the 20% area before maximum owing to the extra bearing surface.

They worked just fine, but IIRC they got squirrelly at distance. SWC made for better long range rounds.

I also liked to load a HBWC backwards with a 38Spl +P equivalent in a 357 case. Those were singularly impressive if you 'accidentally' hit the target stand - it just wasn't there anymore.

I used 2400, H110 and W231.

These days I don't mess with WC's anymore since SWC is more suitable for me and uses almost the same amount of lead.