Science Fair Project Encyclopedia
Precise machining of the muzzle is crucial to accuracy, because it is the last point of contact between the barrel and the projectile. If gaps exist between the muzzle and the projectile, escaping propellant gases may spread unevenly and deflect the projectile from its intended path.
The contour of a muzzle is typically designed to keep the rifling safe from damage, so it is commonly recessed or protected by a convex "crown".
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details