I've never used a 303 but I have killed hogs with a little bit of everything. The .303 cartridge with 180 grain soft point bullet is certainly powerful enough to take any hog you might run across. The only thing I would be concerned with is the accuracy of the rifle. If you can put the bullet within and inch of where you are aiming, at the range you will be shooting during hunting, I'd say go with the rifle. The one thing you don't want to "have to do" with a hog, regardless of the caliber, is shoot him a second time!