I've always figured the recoil difference between the VZ2008s and VZ58s was due to the fact the CSA/Czechpoint uses new recoil and piston springs whereas the 2008s just use whatever is in their surplus parts kits/bins.
I suppose it's possible it's a pressure issue, but never really thought about it.
I will say that if we're talking about .311 bullets (Russian/British use that diameter bullet that I can think of) in .308 full power rifle like a 30-06 or 308, I'd have a much bigger concern about overpressures/potential for overstressing your rifle than with the much lighter powder load 7.62x39 cartridge.
I don't reload as I don't have a place for such a setup right now (or, frankly the time -- part of the reason I like Russian/Eastern block weapons and their low cost of ammo), so this is just my conceptual understanding, but I *think* I'm mostly right... I -- and I'm sure others -- would appreciate knowing if in fact I'm not.
Basically, my understanding is that bore slug diameter between 3.08 and .311 is really a non-issue. What is the issue is the chamber sizing, especially chamber sizing around the neck. And my understanding is that so long as your rounds drop into/seat in the chamber without having to be forced, you should be kosher...