Questor, you may want to rethink what you're asking for.  Any expansion turns the bullet into a parachute.  Pigs are tough.  Even a sow without a gristle plate has skin akin to armor plating.  Thick and tough.  A boar almost defies description when you consider getting a bullet through each side.  At pistol velocities you want penetration, penetration, penetration.  The most I ever go in the expansion department when pigs are involved is to cast 1/2 ww and 1/2 lead and I keep those loads separate to shoot from my carbine, not the pistol.