@grelmar - Zastava M85, how does it compare to CZ do you think? Are you able to shoot military surplus at the range with that too?
Does it make that much difference between SP and FMJ surplus?
The CZ is a better rifle, no question. Fit and finish and how smooth the action is. Don't own one, but have shot a couple, and they're just an all around sweet rifle. But you won't notice any big difference in accuracy. And a CZ will cost you twice as much - which was the deciding factor for me. Not that I don't have expensive guns, just that $1K seemed a bit stiff for a bush/ranch gun that's going to get heavily abused.
I've shot surplus with my M85, and it makes for stiffer extraction. The lacquered cases really grab onto the chamber. My M85 has the improved extractor and firing pin and spring kit (it came pre-installed when I bought it), the ones from CanAm don't have that, but the parts are fairly available and not expensive.
Surplus ammo will have a harder primer, which is the reason for the upgrade to the firing pin/spring. Just gives it a bit more "oomph" to ensure reliable firing. There's also a way (apparently, haven't done this myself) of adjusting the amount the pin protrudes on firing, which should also solve the problem.
The beefier extractor is more of a preventative maintenance thing. The stock extractors have been known to snap over time if you're firing a lot of lacquered/surplus ammo.
The differences between surplus ammo and commercial soft-point are:
Commercial ammo is hotter. Point of Impact will be anywhere from 3" to 6" high at 100m, depending on the brand.
Commercial ammo is more consistent. Surplus ammo was loaded to fairly broad tolerances, back in the day. Bullet weight and powder weight can vary as much as 2% each in the same spam can, which when added together can make pretty big differences.
Commercial ammo tends to be brass cased. Which makes it easier to extract. Oddly, my favourite x39 hunting ammo is the Hornady SST ammo, which is lacquered steel cased. Steel v. Brass does not affect accuracy - just how smoothly it extracts. This is not an issue in a semi auto, which cycles rapidly enough to pull the steel cased ammo before it has begun to cool, which is really what's creating the stickiness. No matter how fast you might be with a bolt, a steel case will have begun to cool by the time you work the bolt to do the extraction.
Corrosive ammo isn't the end of the world for any gun, you just have to practice regular cleaning - the rifle will need to be cleaned the same day you fire it if you're using corrosive. And bolt guns are a LOT easier to clean than semi-auto gas guns (and the SKS is pretty simple to clean anyway), so it doesn't phase me in the least.
The best thing about surplus ammo: When .22 was in short supply, I'd just load up my SKS with surplus, and pop gophers with that, the ammo was cheap enough to do it.
Cheers.