I never tested this prior to changing out the gas rings and the extractor. However after the change I did test it. 100% function. I shot 147 MFS Russian steel cased ammo, 155 Hornady Steel match, some 168 and some 175 handloads. I was only shooting at 40 yards or so due to the longer range being busy. Not far enough for accuracy test, however the paper results looked as I expected even at 40 yards.
Everything shot poorly for accuracy. Except the 175 SMK reloads. When I say poorly I don't mean shotgun, but an inch to a few inches. The type of accuracy that many could write off as the trigger, if I had a better scope etc. However I knew this wasn't the case. As I've stated previously in threads on these rifles. 18.5" barrel, 1:10 twist. You have to reload hotter. This is why I generally like a 20" or longer barrels and actually prefer a 1:11.25 twist. Although with a longer barrel the 1:10 twist likely wouldn't be an issue. So the 175 SMK was loaded 43.4 varget. It shot one small hole. The rest were all over the place with the 168 and 175 off the shelf Gold metal match being smaller, but still not very good at that distance. At 40 yards you can still get an idea of how the rifle will shoot. Just expect it to get larger farther out. The 168 Federal Gold was one of those rounds that many would likely think they could shrink with a better trigger or scope etc. But I know that's not actually what was going on. So exactly what I had expected. I will load up some more of those 175 smk rounds which I use in pretty much all of my other 308 rifles and test out at 100. I won't bother wasting my time or money with any of the other ammo and this rifle.
The only issues I have with my 102 are the 6061 non anodized upper/lower in terms of I would prefer 7075 anodized for quality/longevity reasons. Along with the trigger being complete and utter crap. The trigger really does suck. Add in the odd ball barrel length thanks to our laws and the attempt to make the rifle as short as possible for NR along with a twist rate that I would prefer not to have and there are the primary issues with the 102.