I actually have quite a bit of experience with this. Pigs up to around 200 pounds can be taken with broadside shouler shots (not behind the shoulder but through the shoulder) with the following:
Federal 55-grain Barnes TXS
Cor-Bon 53-grain Barnes TXS
Federal 55-grain TBBC (discontinued in civilian version, get the LE TRU Bonded Soft Point)
Black Hills 68-grain OTM (a real killer on pigs)
Hornday 75-grain TAP
I shot one with a conventional 55-grain JSP, won't do that again.
Not to say that Nosler Partitions won't work, just never tried them. All of the above bullets will tear up the onside lung, the TSX bullets take out both lungs. Pigs typically go down on the spot, some run 10-20 yards.
I have had poor luck with neck/spine shots. Pigs go down on the spot, but for some reason they just lay there and kick and flail around until I can get to them and head-shoot them, and I swear that they don't taste as well when processed, which I attribute to a build-up of lactic acid in their muscles, adrenaline, whatever, I don't know.
Wait for them to pause, put it square in the shoulder, and you should have meat for the larder. The only other caveat I would add is that I have never shot a pig over 200 pounds with a .223; however, most of the Texas pigs you will probably see will not go over that. I know there is a lot of talk about 350-400 pound wild boars, but I have never seen one in Texas. Big boars are smart, and it takes a lot of food to grow one to herculean proportions.