I agree. Your rifle and load is absolutely fine for pigs. The problem was the shot you took, and the resultant hit. I shoot them all the time with my 7-08 using 140gr Sierra Gamekings. I've taken dozens of them with my little 222 as well using 50gr v-max bullets (all head shots though). Good shot placement drops them in their tracks or leaves massive blood trails for very short distances. You likely hit high in the lung area, and the lungs filled up with blood, but none leaked out until the pig laid down. Seen it many times with rifles and bows.
Like others have said, I like the burr of the hear with the pig looking slightly away. My 7-08 will literally pop their eyes out of their head. But for a body shot, i look for the quartering away shot and put the bullet low, right behind the shoulder. If they're running, I put lead in the air. A hit pig will die, and that's a good pig here in Tx. Sure, it's always nice to recover your game. but the fact is they're not a game animal, they're a nuisance animal. So you did the landowner a favor, whether you recovered the pig or not.
One thing about it, there's plenty more where that one came from!
Jay