This model was designed by Captain Slug and reposted as permitted by his CC-NC-SA license.
The SCAR, or String Centering And Rifling, is a muzzle attachment for spring-powered Nerf blasters that improves accuracy by preventing darts from fishtailing after leaving the barrel.
This is one of the slickest and most effective SCAR's of them all; it may be a little heavy, but it gives you six strong strings and a clever friction-clamp collet mounting system.
Print the Cd, Nd, and Sf parts, and the appropriate VF1dc part for your barrel. Please print the Cd part in blaze orange for safety.
VF1dc is sized for the 5/8" OD aluminum tubing used in the Caliburn.
VF1dcNexus is sized for the barrel of the Dart Zone Nexus Pro blaster.
The other VF1dc parts are sized for common brass sizes, for use with brass-breeched blasters.
Instructions: http://captainslug.com/nerf/SCAR3%20Assembly%20Instructions.pdf
You'll need some fishing line and something sticky, like a stick.
This worked great on my Caliburn Sniper build on my YouTube channel!