The 308 will feed fine from a long action previously chamberd in 30-06 , the US Army's sniper rifle system (the M-24 anyway) is a long action Rem 700. I built a couple 308's on long action just becuase I was wanting to shoot the 175-190 gr Bergers and seat them way out.
Also for years Savage made the 308 on long action with no troubles.
I say go for it and don't look back.
As far as action being the stiffest from the factory , I'd say that its close between the Weatherby Vanguard/Howa and the Winchester M-70. , the Weatherby MK-V is probably in their somplace but its fat bolt I feel reduces some of its "stiffness"
But unless your haning some realy fat , long barrel off of it the Stevens and Rem round action asre plenty stiff enough.
The "strongest" as far as whay can be loaded in them I would say is is so close between the Savage/Steven , Rem 700 and Howa/Vanguard that by the time it came to blow one up they would all likely be having some very serious troubles. , the lugs on all of them are very close is size that the lugs are what takes the abuse.
But again , I find myself saying this more and more , if your going to be buying an action to build on and you plan to have it built correctly with a full action blueprint , save yourself , your smith and your wallet some trouble and order a custom action from Pheonix machine
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