Barnes Triple Shock Solid Copper X Bullet
I have worked up loads using Barnes Triple Shock X-Bullets for pistol (XPB) in all the various grains that Barnes has to offer and have settled on the 275 grain bullet!
These are solid copper and each have six petals that peel back as razor-sharp 'cutters' that about double the diameter of the bullet as they peel backward.
If you notice those peeled-back petals, one can see that they are very thin at the front and get thicker as they go back which helps them each to stay attached to the main base. There is even a ridge along the midsection of each pedal to add strength to each petal!
With the high velocity of these bullets after peeling back, there is guaranteed major disruption of bone, arteries, ligaments, veins, nerve bundles, etc. These bullets are fairly expensive compared to others, however there is no jacket to separate from a core -- they naturally want to stay together!