Craig: The usual rifles chambered in the British 303 caliber are not as strong as those chambered for the 270, unless you are talking about the Enfield's P-14 action. The other rifle/action you normally encounter in the 303 caliber is the SMLE, usually a No1 MkIII or a No4MkI. Neither of the later two are strong enough to handle the pressures of the 270 cartridge, which is basically a 30-06 necked down to 270 caliber.
In terms of caliber to hunt hogs with, Coug2wolfs would be a better judge than I but I would think that a 303 with a 180 or 205 grain bullet should suffice for those critters. I sort of think a 270 might be a bit light for them but I do not have the experience with hogs and either caliber to advise you properly. Maybe Coug will add his experience to this answer. Mikey.
