@Star_Treasure: No, unfortunately snap shots are only one shot. It's not something modders can alter.
@Surrealistik:
The humanist super soldiers cannot react, their weapons only have autoshots. It was not a fluke.
As for the reliability of HMG type weapons, given the likelihood of getting screwed with the 0-200% rule, which is what these weapons are using by default and what prompted the comment. It's false to claim that the sniper is more reliable. Until you reach 100% (which means firing acc = 100 on a regular sniper rifle), you actually have more odds to miss your one shot because of the quadratic dependency on accuracy of the sniper rifles and the forgiving nature of the HMG.
Ex.: at acc = 99
- Sniper rifle accuracy is 0.01*99^2 = 98%, so 2% to miss
- HMG chance to hit is 49.5%, chance to miss is 50.5%, to the 8 for the chance of missing all 8 is 0.42%
Once you factor the chance of the RNG screwing you over on the damage roll, it becomes even more significant.
Still at 100 acc:
- Sniper rifle with Normal-PS ammo: 30-36+100/4 = 55-61 damage
- HMG with Normal-PS ammo: 55-65 damage
The damage being similar, you have similar odds of rolling under the armor value. But if you crank up the accuracy of the firer beyond 100 to increase the damage of the sniper (thus reducing the odds of not doing damage), the odds of missing all HMG shots become even smaller, the odds of hitting with multiple shots increase, and the HMG pulls even further ahead. The vulkan pushes the advantage with the 20 shots, despite the reduced accuracy.
Sure, if you make the sniper rifles more dependable, they get more dependable (but they lose some of their ability to roll really high, which is where they shine with very very high accuracy soldiers to overcome very tough enemies).
With the current rule, you are more likely to get screwed by the RNG on your one damage roll with a sniper rifle than to miss all and/or get screwed on multiple shots of the HMG. You hit often enough that some of the hits will likely roll you good damage, plus each hit does a little bit of armor damage, helping the next to punch through.
The niche of the sniper rifle is with really good accuracy soldiers to push the damage really high, but that is rarely required since the Vulkan can whittle down common power armored foes reliably. Or those trick shots where you have soldiers in the zone, which given your preference for smoke and snipe, shouldn't be much of an issue (it isn't even for me, and I play pretty aggressively with ~50% melee soldiers). So that leaves reaction fire, but with the decreased accuracy and still high TU cost, it's not great either.
The hunting rifle and the like are great for training gals (one hit, regardless of damage, is a chance at a stat increase) and reaction fire (they tend to perform better with snapshots, although the damage is worse), the HMG does better with applying damage at a distance (and I enjoy blowing away the cover too, without blowing away the items like with HE damage).
Anyhow, that's my experience and the statistics to back it up. If you are enjoying the sniper rifles, great for you. I just wanted to pitch in for those weapons which, on paper, might not look too great (crap listed accuracy and really heavy) but can also be really useful (and lead to maniacal laughing while blowing stuff away).