The angle iron in the front is made from commercial 3/4 x 4 angle iron that I bought from a oil field machine shop where I worked. After squaring it up in the mill 2 oversize 5/16 holes were drilled on 4 inch centers for holding the V blocks to the angle. The distance to the front edge was 1/2 the thickness of the V blocks so they could be lined up against the fence on the front (top in the accompanying photo). The fence is a commercial hardened and ground parallel, the spacing of its mounting holes was also 4". The V blocks are made by Eron and I think they can still be purchased from industrial suppliers.
In use and also when finishing the angle iron a piece of 2 inch long brass bar stock was used between the front vice jaw in the mill and the leg being held in the vice. This insures that the angle iron is flat against the rear vice jaw.
The round bar on top is 16mm (.6299 inches) stainless that I had on hand 5/8 inch bar will do as the Krag bolt is approx. 5/8. This bar is 5 1/2 inches long and worked well with 4" inch hole spacing (3/4" from one end).
To set this fixture up set one leg in the mill vice with an appropriate spacer between the bottom leg and front vice jaw. Install the front fence to line up the V blocks, set the barreled action in the V blocks. After getting the hold down studs started in the bolt blank you can indicate the bottom of the action level then tighten the nuts under the angle iron. After all this is done the stock can be attached to the barreled action and milling angles can be done to the stock.
The second photo shows the fixture from the back of the machine after the front pillar and front trigger guard cuts were made. The 5 degree angle is for the last cut on the rear trigger screw (5 degrees from level).
That angle iron in the rear of the first photo, I found it in a tool box when I was putting the new one away. The hole spacing in it, you might have guessed, 4 inches. That is trouble with getting old, you forget stuff!

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