Just about everything out there drops off pretty quick past 400yds. It's a different ball game and isn't something you'll just walk out and do right away (though you may surprise yourself your first go with the right tools). But yes, the 243 will definitely get there. They shine brighter from afar with a barrel twisted for heavies, but factory tubes and 87gr vmaxes can do nice things. I grab a 223 more than anything these days for target shooting up to around 800yds. Easy and affordable to shoot high volumes to practice.
I have a bit of a soft spot for the 25-06 as a hunting rifle, as it was my first. The downfall of the quarter bores, however, is the lack of bullets well-suited to long range shooting. The best I've used for the job is 115gr nosler ballistic tips. They've shot well for me, but they're nothing even noteworthy for LR shooting and are pricey for what you get. With LR in the mix of your intended applications, I'd stray from the 25-06...if you're going with a long action, I'd focus on the 280. JMO.
Last edited by Big Z; 05-27-2014 at 07:50 PM.