I'm looking to pick up a rifle for hunting at my place in Belize (Central America). Firearm licenses are tough to get, so I'm pretty much limited to 1 rifle. I'll be hunting small white tail (up to about 100lb) and red brocket (around 50lb) from a stand on the edges of open savannahs and power line cuts. I'd like to be able to get out to about 300 yards for a kill. My first thought was a .270 Winchester for the range, but knowing the game is small, I'm wondering if I should choose a smaller round. Any recommendations? I will need it to be a relatively common caliber, as availability of ammo can be an issue.