This is a reskin of hunting rifle, staying close to original but higher resolution and more details.
Main textures 2k, workbench mods original resolution.

Make sure you :
How to enable modding

• Navigate to your Fallout 4 Folder at the following location "Documents/My Games/Fallout 4"
• Within this folder you'll find a number of .ini files.
• Open (or create, if missing) Fallout4Custom.ini with your favourite text editor (we use Notepad++).
• Add the following lines to your Fallout4Custom.ini[Archive]bInvalidateOlderFiles=1sResourceDataDirsFinal=
• Save and close Fallout4Custom.ini
  

from wiki
then either install from nexus mod manager(easy) or, manually copy files to fallout install directory.
No esp activation needed, this is only texture mod.