I'd recommend making a small batch and testing.
Russian/Combloc .30 caliber/7.62 projectiles are .311, and Western 7.62 .30 caliber projectiles are .308.
They'll fire safely, but might not engrave the rifling well, and provide some ability for the gas to blow past the bullet giving poor velocity or accuracy. Or, depending on the base design, if it has an open tail with exposed lead, the bullet might swell a bit on firing and obdurate in the bore just fine and shoot well.
Some have had accuracy results better than milsurp or bulk commercial 7.62x39, because in their rifle the higher quality American made bullet was better and that outweighed any difference in diameter. Some had groups that doubled in size because of the undersize bullet.
It's the kind of thing that works on a case by case basis, so I'd load up 20 rounds or so and test first. AK and SKS manufacture is somewhat variable, and could have barrels and throats from .309 to .312 etc.
There are .311 and .312 American made .30 caliber bullets out there, but obviously they're going to be much more rare and expensive than the .308 ones. Or a lot of them are going to be hard-cast lead with lube grooves etc.