Armed and Dangerous is a trophy in Fallout 4, available on all platforms.
Requirements
Create 50 weapon mods To view your progress toward this achievement - open up your PipBoy and go to DATA, STATS, Crafting.
Notes
Each mod you build for one weapon counts for this achievement. Which means you can get a regular pipe pistol and create 25 mods for it, and all 25 of those mods count towards this achievement. You are not required to mod 50 different weapons.