Sorry about the expression - I stole it from the fellow who does the "Into the Night" hunting videos (good viewing).
These three pigs were felled with TWO shots.The first shot got the spotted boar in the middle of the shoulder, exiting behind the far shoulder, and collecting the sow that had conveniently positioned herself for the shot. The second sow copped it as she ran. I'm not too sure which of the sows made the twosome. All three pigs had exit wounds, so the bullet of the double made it right through both pigs, whichever one it was. All were shot from the right side, so the wounds on the sows do not give the full story on shot placement.
This was with 176 gns bullets in .30-30 at 2200 fps. The hollow takes about 10 gns of bullet weight. Alloy is a little harder than #2.
I have posted before about using hard cast hollow point .30-30 bullets for hunting. There seems to be a widespread view that hard bullets will shatter and be ineffective. My experience has been that while the noses of hollow point bullets certainly break up, they do not do so all at once and the shank of the bullet can penetrate a long way. The shrapnel from the broken noses certainly does a job on pigs of all sizes.
This was my second double for the week, though the other was unplanned.
By way of admitting that penetration is not always forever, I can relate that I shot another large sow later in the afternoon, but the bullet just barely failed to exit. It was visible as a skin lump on the far side. It had been through both shoulders, bore the marks of a serious encounter with bone, and was ground down to 56 grains - I'd say it did a lot of work.
Truth is, I am seriously happy with the hard cast HP .30-30 bullets.
You are only as good as your library.