Finally finished instructions for this fully automatic Lego R99. Link in comments. : r/apexlegends
Make an Easy Lego Gun. : 7 Steps - Instructables
Review - The BrickGun Book - Jeff Boen - BrickNerd - All things LEGO and the LEGO fan community
Elite Weapons for LEGO Fanatics: Build Working Handcuffs, Body Armor, Batons, Sunglasses, and the World's Hardest Hitting Brick Guns: Amazon.co.uk: Hüdepohl, Martin: 9781632205063: Books
Badass LEGO Guns: Building Instructions for Five Working Guns: Hudepohl, Martin: 9781593272845: Amazon.com: Books
How to build LEGO guns that work!
Lego gun instructions: Page 1
Lego Pistol Working Instructions, Jobs EcityWorks
BrickGun Book | No Starch Press
How to build LEGO guns that work!
Lego artist David Turner denies glamorising guns - BBC News