Sniper Elite: Resistance

If you're picking up and using weapons out in the field, you'll easily unlock this without even trying. Anytime you see a weapon available to collect, grab it and kill a Nazi with it. Sniper rifles are especially useful to experiment with anyway, so just keep nabbing weapons and wielding them until this unlocks. You can also switch weapons at any workbench, or change your loadout before each mission – chopping and changing weapons will help towards this and the Master-at-arms (30G) achievement.

If you're picking up and using weapons out in the field, you'll easily unlock this without even trying. Anytime you see a weapon available to collect, grab it and kill a Nazi with it. Sniper rifles are especially useful to experiment with anyway, so just keep nabbing weapons and wielding them until this unlocks. You can also switch weapons at any workbench, or change your loadout before each mission – chopping and changing weapons will help towards this and the Master-at-arms (30G) achievement.

Refer to the ‘Mop Up’ section in the roadmap for a farming method to make this go a lot quicker.

To check your progress, press then navigate to Service Record > Medals > Weapons and Items and look in the first section to see your medal progress.