Have used thousands of 125 and 130 grain 30 cal bullets for shooting pigs. The Speer 130gr hollow point is extremely popular with pig shooters in Australia. Huge hollow and I suspect the jackets are a little thicker than the 125 TNT Speers.

Currently still using 130gr Taipan bullets which I find a little soft so I don't shoot larger pigs in the shoulder but try for shots behind the leg or head/neck.

I used to use 150 grain bullets but had too many pass through which is frowned upon on the grain and cattle properties that I shoot on. Seem to be able to keep the 125/130 bullets in the pigs which results in spectacular kills.

I do not believe the heavier bullets are necessary unless your only quarry are large mud-encrusted boars. A firefight with a mob of pigs usually involves a large sow (shoot in the head) and a running battle with mid-sized pigs. Heavier bullets are not required. While you can drive them at 3000fps from a 308W I find I get good results at 2750-2800fps. Maybe they penetrate a little better before fragmenting. Also the lighter recoil aids recovery and you may get an extra shot off before the engagement is over.

Another good bullet for pigs is the Speer 150 30/30 bullet at about 2600fps. Very accurate and will stay inside a pig.