The only DBM system worth a damn for mass-market rifles is the AICS, which uses the AICS magazines and either the Badger or Surgeon bottom metal on conventional stocks or simply an AICS stock from AI themselves. There are some other DBM systems for mass-market rifles, but in general they are inferior to the AICS. If you don't care about that, some of the rifles do come with proprietary DBM systems.
I have thought about a lightweight long-range concept, and the problem you will run into is that, quite simply, many of the things that make a great long-range rifle also make the rifle heavy.
For a new long-range shooter, I strongly recommend not trying to learn on a "compromised-purpose" rifle. There is a good chance that without long-range experience he will make the wrong compromises and it will slow down his learning curve because it will be a worse LR rifle than it could have been.
However, with that out of the way:
If I were to do this with a healthy budget, I would use a Manners lightweight stock such as the MCS-T (2.1-2.5#), Surgeon bottom metal, an approx 22" med or light Palma contour barrel, and a relatively compact 10x or 12x scope. It would be chambered in .260 Remington so it would still exceed .308 long-range performance and would have plenty of high sectional density bullets available for hunting.
If on a budget, I would strongly recommend the Tikka T3 series. They cannot be beat for value for the money in the sub-$1000 regime. The T3 Lite meets your criteria other than the Pic rail, which you can buy aftermarket (e.g. the EGW one)
Last edited by Zak Smith; 05-14-2010 at 11:49..