Depends on the accuracy you’re looking for, loads you’re running, type of shooting you’re doing, if you’re over cleaning and using a bunch of hard core chemicals in your barrel, etc, I’d say a safe estimate is 8k-10k. Compare that to a 6.5 (2500-3500) and a 6mm (1500-2500)
As far as projectiles go, I never shot anything other than 175gn SMK’s with 44 gns of Varget. 1:12 , and 1:11.25 twist worked fine for that. Great results and had no reason to try anything else. They worked. 168’s SMK’s shoot really good out to 600 or so then they kind of apart. Some may disagree but that’s been my experience.
175 SMK’s , 44gns Varget works pretty well in damn near every .308. Obviously you need to test that yourself. I typically start out load work up around 39.5 gns of Varget and work up to around 45 gns in .5 gns increments typically I get flattened primers and sticky bolt around 44.5 - 45 gns. Never fails, 44 gns is typically where I settle in. Lapua Brass.
190’s are a definite 1:10 IMO.