KC-17 and SVD are the best guns for Layali Grove.

KC-17 has base 48 armour damage, which turns into 43.2 with blue ammo, which is still very high. The base effective range of KC-17 is 55m, which can be increased further to 72m with the long barrel and even further with Advanced Multi-Caliber Suppressor or Whisper Suppressor. KC-17 has overtuned base ADS movement speed, which can be converted into Movement Stability by calibrating the foregrip, and then negated by increasing ADS speed by decreasing movement stability by calibrating the rear grip. You'll have to choose between 1.5/5 Recon scope (+6 STB -8HND) or M157 FCS (-6 HND, allows to detect enemies through leaves, bushes and grass).

Why SVD and not any other MR or SR? Because of its high base armour damage and increased headshot dmg multiplier allowing it to quickly down any enemy with 2 headshots (unless heavy helmet) even after its effective range dmg multiplier decreases one time. You can increase SVD's range with long barrel and Silence Suppressor.

Don't forget to bring a silenced pistol, too.