Before you start complaining for such a noob question, I already now it's about the round mass, speed and sharpness.
What I want to know is, how do I effectively make a strong hit.

For example, my sniper rifles fire rounds with mass = 4.45, sharpness = 35 and FireVelocity = 1000. Now, when I shoot someone at a decent sniping distance, I barely damage 2-15, even if it is a headshot. Even though I can seriously go through soil, concrete and strong terrain, I can't kill in a headshot, or at least damage more than 15.

Could you help me to give it more punch?

It shoots the round to fast, the maximum fire velocity you can get where the gun will still work properly is about 400-500, but trust me, a gun that fires round of that mass with that sharpness will be plenty powerful with a normal velocity.

I knew velocity had something to do. Most of the time I shooted someone it went through it. Just like that.

Edit: It solved the issue of going through enemies, but it still lacks power.

Have it fire multiple particles, creating multiple wounds.
The var for this is under where the round is defined.

Going to try that right now.

Edit: Holy sh*t! Set particle count to 4 and killed a dreadnought in 1 hit! That's way too much power. I'll set the particle count to 3, lower the mass and speed a bit.