In my opinion two "factory" rifles have made custom rifles a luxury instead of a need (for reason that Larry and Jay pointed out; magazine length, twist rates, stock, high QC, triggers, fasteners, bedding, accuracy, etc.)
Light weight rifle - Barrett Fieldcraft
Sporter weight rifle - Seekins Havok
I've had many friends that aren't into rifles shoot one of my rigs and ask how to go about getting a custom. I always point them in the direction of Barrett or Seekins depending on their needs.
Right now a really interesting sporter and lightweight pair would be the Seekins Havak PH2 and the Seekins Havak Element, both in 6.5 PRC. Seekins put a little thought to it with an extended detachable mag for the PRC with a 3.14" length.
I'd like to play with one of the Element rifles. Neat concept with the aluminum action. It's light, I do think the stock will be a little bulkier than I prefer on a lightweight when carrying it in my hand.....I'd like to prove myself wrong though.
