I just received a McMillan stock for a LH 338 I had made up. When I drop the barreled action into the stock I can move it back and forth about 1/8 inch. It stops when the rear of the tang hits the stock.
This doesnt appear to be correct to me as I was always taught it should sit square against the recoil lug. Action is a Ruger Mark II 77. Magazine and bottom metal fit nicely.
Also, when my smith did the barrel job he shorted the shank portion of the barrel to reduce a little weight and there is a large gap around the barrel about 2 inches out from the front of the action. What is a good bedding material to use that will blend in with the stock matt black color of the stock?

I have a similar challenge with my McMillan for a CZ zkk602. There the barrel channel is put .5" too far back which implies that the barrel recoil lug misses its molded in depression.

For the bedding mass, I have heard good things about marine tex. I have also heard that there are some pigments that can be bought at a local paint shop to be blended in the bedding paste.

Sincerely
Daniel