I've only heard good about Dave Young and He's doing a 300 RUM build for me on a R700. He likes Mark V actions and has probably worked on hundreds of them, maybe thousands, and he is also 30-378 fan. He tried to talk me into one but I opted for the 300 RUM. He probably has as much experience and knowledge of the Weatherby's and Mark V's as anyone.
You will never know how much it has cost my generation to preserve your freedom. I hope you make good use of it.
~ John Quincy Adams