Just depends on what cartridge you want to go with. In a short action, I’d go with a 6mm Creedmoor and in a long action, I’d do a 6mm/06. The short action M70s have a 2.8ish box. The box is actually longer, but Winchester puts a spacer in them. The spacer can be removed and the ejector shortened to allow a longer OAL, but I’ve read of mixed results with feeding when doing so. Depending on what price you can find a donor M70 at, you might also consider a Montana Rifle Company action. They are very M70esque and their short actions come with a 3” box.
I think Redneck is the resident Model 70 expert. Might PM him.
John
Lots are recomending the 6mmCM on the SA M70. Ammo is readily available now, fits the mag etc. But :
Me I'd swim against the tide; remove the spacer etc. and go 6mm Rem, or the AI version for a little more capacity and reach. or a 257 Roberts,
or Better Bob Improved 3"w/ long throat. Also the M70 SA would be an Ideal home for a long throated 260 . Just get the twist right on these.
