Well, I would re-think the dual competition/hunting uses. I bought a Rem. 700 and sent the action off and had an M40A1 built and, like you, I wanted to use it for both competitions and hunting. I competed with it for a few years in F-class competitions and hunted with it once....and ONLY once. The thing was so damn heavy that I told myself that I'd never do that again. Will it shoot? Of course it will. But getting it from point A to B is a nightmare. I couldn't imagine hunting with it in the mountains let alone flat ground.
I'll second this. Imagine what the Marine Scout/Snipers feel like carrying one around 24/7, eating, sleeping, humping (secure the dirty minds, a Marine vet will know what I mean), low-crawling hundreds and sometimes thousands of yards in a guille suit with a 25lb M40 sniper rifle in 110+ degree heat. All while every bad guy and his 10 brothers is doing everytyhing he can to hunt you down like a rabid dog because snipers are the most hated grunt on the battlefield...well, I'd say it'd be one tough way to make a living.[:@]
If you want a rifle for long range competition, you should build a rifle specialized for the type of competition you plan to participate in. If it's long range bench rest shooting, such as 1000 yard BR, you'd build it specifically for that so that you can be even stand a chance against the competition. I don't know enough about the different competitive diciplines to give you a good recommendation, but if you search the net you can find tons of info about the various rifle diciplines and what type of equipment is involved.
If you want a rifle for hunting, then you should build one for hunting. The specs for a practical hunting rifle are MUCH different than a competition rifle. That's not to say that a custom hunting rifle with a sporter-weight barrel and stock can't be remarkably accurate with hunting bullets, but it's not likely to be competitive with the full out competition guns you'll see in any serious event.
Good luck, and Semper Fi from a former 5811,
Mike