When I find a LH standard bolt face M 70 action, I may well build a 9.3x62.

I think 10# is about 1.5# heavier that I would be aiming for.

I would not go any shorter than a 23" barrel, not because of cartridge considerations, but because of what works well with the Legend stock (which I think is a grand choice for your project.)

I would play around with barrel contours starting with a muzzle diameter of .75", which would give a wall thickness of almost .20". But I would go with a steeper taper than most factory rifles, which mostly taper at about .008"/".

Have you thought about recutting the tang into the pre-war style and building up the bolt release tab? I think it creates a good look that works well with the contours of the Legend stock.

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