Stan
The only boar I've ever shot was from the safety of an elevated deer stand; and it wasn't large at less than 200lbs, but one 150 grain 30/06 pill thru the ears did the trick. My son has killed several, all one shot kills, with his little 257 Roberts and 117 gr. bullets. Most of my BIL's wild pig count are the result of his 35 Rem and 200 grain Coreloks; but then he has also taken a few with his 6mm Rem. Like you, if I'm on the ground in tight cover, give me a heavy bullet; but I honestly believe his experience with the boar above was an aberration, maybe the bullet just failed to perform? The largest wild boar I've seen personally was also killed by my BIL; but we have no idea how much it weighed. The only scale we had handy was a 300lb cotton scale; and even field dressed, that scale bottomed out before we got the hog's head and shoulders off the ground. All I know for sure was that it was so heavy its weight significantly bowed the tail gate of his little D50 Dodge as it was loaded.