Ar15 muzzle cover

thingiverse

This cover is designed to prevent obstructions from entering the barrel, and if constructed properly, is even waterproof. Simply print it to scale, and it should fit just a little too tightly to slide over the end of the muzzle brake. Heat it with a lighter down the sides, and slide it on. When it cools, it will shrink around the muzzle. Then simply leave it in place until you're ready to use it. If time is short, fire away - it will be destroyed instantly. This muzzle cover only works with the original A2 birdcage flash hider, and others of identical outside dimensions.