This is just stupid. Sniper shot and he keeps running like nothing happened
Red mist in this one suggests it doesn't guarantee a hit was registered. M24 should always 1-shot AFAIK.
If it doesn't they should buff it.
On the steam discussions: [DEV] Hitreg fix incoming
Yesterday we found a pretty significant issue with Insurgency: Sandstorm's hit detection code.
We have tested a fix for this a few hours ago and we hope to be able to push it live on Thursday where you should see significant improvements.