As long are the rifle likes the ammo (accuracy wise), then any factory ammo should function safely. The BAR is also well known for its excellent reliability, so as long as you keep it reasonably clean and properly lubricated (meaning enough lube, but not too much, especially in cold weather) it should function fine.
The BAR is also pretty well known for decent hunting accuracy, with < 2 MOA groups being the norm. I wouldn't EXPECT any greater than this, but I've also heard of guys getting sub-MOA accuracy from the BAR. Probably the biggest thing hindering the BAR's accuracy is the relatively crappy trigger pull. It's not as bad as the worst "lawyer triggers," but it's pretty bad by my standards (I like my hunting rifle triggers at between 1.5-2.5 lbs). My pure estimate would be that they run in the 5-7lb range from the factory. A gunsmith can reduce and clean up the trigger a bit, if you can find one that will do the work (for liability reasons).