Ive done this 4 times. A .223 with a 0 magnification red dot or iron sights is what I found to be the most fun. Don't use a magnified optic. Shotgun with buckshot also works well for pure knockdown power and makes up for the lack of accuracy brought on by all the movement but you're gonna spend a lot more time reloading if you use a shotgun. Your pilot will probably require you to have a brass catcher bag on your AR.
As far as leading a running animal, that's tricky. You will likely be coming at them from different angles. Most of the time the pilot will have you so close that you don't need to lead at all.
One trip we had lots of single file groups in big fields. The pilot would get relatively high above them and come in from behind. He taught us to "reverse lead" in this situation since we were coming in at a much faster speed than the hogs. That meant we had to aim slightly behind them. It didn't sound logical at all but it worked.
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"Political Correctness is a doctrine fostered by a delusional, illogical, liberal minority, and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."