So far I am not convinced that the battle rifle is better than the assault rifle in todays combat. I see alot of "if they are in this terrain or that terrain the battle rifle is better". But a soldier is issued only one rifle to do it all. And I still believe that in MODERN WARFARE the assault is the best choice.
Ah, but now you're changing the question. You opened with some vague comment about choosing a rifle for "protection," not what to issue to "modern" soldiers.
Bigger bullets wreck things better than smaller bullets, and something like a 30-06 will do more damage (and at greater range) than something like a .223. Believe it or not, there are a number of things that a rifle cartridge can do that the smaller bullet can not.
Whether this matters to you is another question entirely. Hell -- whether this matters to the US Government at all is in question. I was at the range yesterday and saw most of a squad's worth of rangers from the 1st Rgr Btn out there goofing off with their privately owned weapons. I borrowed one guy's (piece of crap) Century Sporter wanna-be HK91 (and let him shoot my M1A), and watched them shoot damn near everything -- lots of pistols, a .308 bolt-action rifle, a couple of SKS's, an AK or 2, lots of very "tactical" looking shotguns (including pistol grips and all the goodies), etc. I wasn't impressed.
Not only were there a
ton of safety violations, these guys simply couldn't shoot. Blasting away at a metal folding chair from 15 yards with 2 shotguns and only about 1 shell out of 3 hit the chair! Lots of fast shooting at 50m and 100m targets, but no precision fire. Hell, I'm way out of practice but I could keep a coke can jumping with every shot at 50m with my (new to me) M1A and iron sights until the thing blew apart -- much better than I saw from these guys in an elite unit. (Note that I was once judged not-good-enough to go to Ranger bat and had my orders to 2nd Btn yanked -- I've got shoulders that dislocate slightly when you tug on them -- but this isn't jealousy. These guys truly sucked.)
You may be right -- marksmanship and powerful rifles may be "obsolete" in a "modern" context. But I'm worried about what might happen to these guys against Afgan sharpshooters with their "obsolete" Enfields.
Those "useless in a MODERN sense" .303's can probably wreck a Hummvee's engine block at a few hundred meters for starters. But then, I'm sure massed mostly-unaimed .223 fire will get their heads down while we use arty to blast the hell out of any-and-every outcropping of rock. Those Afganis don't stand a chance.
As always, in my (not so humble tonight) opinion.