Update to thread by OP:
Gunsmith talked me out of the planned build due to concerns over possible inherent reamer designs affecting accuracy in the chosen parent case. After receiving the PTG 4" bottom metal, we changed focus to a 6.5 SAUM. I did indeed buy the Nucleus 2.0. I went with Accurate Mag DBM and McMillan Game Warden (original) stock for weight savings. I have a long action with an Ultra Mag 3 715" box. I wouldn't have went this route without the CRF. I sent dummys with COAL of 3.080" and the smith told me I needed to go deeper for stability and to allow for throat erosion. I was at the base of the neck plus a little with the base of the bullet, but the long boattail was still inside the neck slightly. That was with a 140gr VLD. Smith wasn't willing to risk his well-earned reputation on an accuracy issue created by a novice wildcatter. I told him to do what he does to make it work to it's fullest potential. I can't tell you how it works/functions/shoots because it's still in production, but we should be getting close. I can tell you the McMillan stock was ordered with cutouts for the Nucleus, a 3B Bartlein, and the Accurate Mag bottom metal. I had already shipped the barrel when the stock arrived, but the bottom metal DID NOT fit. It's costing me $300+ for inletting, and the smith said he sees this regularly in McMillan inlets. I received a Mesa Precision stock inletted identically a week after I shipped the McMillan with bottom metal. I love the Mesa stock and would like to see how the bottom metal fits that one just for grins. The project MIGHT end up wearing the Mesa stock depending on whether less inletting is required vs what was needed on the McMillan. The Mesa is only a couple ounces heavier, and the only thing I'm not absolutely in love with is the blocky verticle pistol grip. I have small hands, so the McMillan definitely fits my hands better. The Mesa seems to be a much more solid stock and the finish is amazing. I can't say this is an apples to oranges comparison, however, because I ordered the McMillan in a lighter fill, so obviously it's GOING to feel less "solid." That's the cost of saving a couple ounces. I will update once I have rounds down range.
