Free-floating barrel
From Wikipedia, the free encyclopedia
A Free-floating barrel is a specific design technology used in highly accurate rifles, particularly match grade rifles, to increase the accuracy of the weapon.
With normal rifles, the barrel rests in contact with stock. In particular if the stock is manufactured of wood, environmental conditions or operational use may shift alignment of the stock, which may cause the barrel to shift its alignment slightly over time as well, altering the projectile flightpath and impact point.
A free-floating barrel is one in which the barrel and stock are designed to not touch at any point along the barrel's length. The barrel is attached to its receiver, which is attached to the stock, but the barrel "floats freely" without any contact with other gun parts, other than the rifle's sights. This minimizes the possible mechanical pressure distortions of the barrel alignment.
Alternatives include using a stock manufactured from composite materials which don't deform under temperature changes or humidity changes, or with a wood stock using a fiberglass contact area (so-called glass bedding). Stocks which contact the barrel are still popular for many utility weapons, though the most accurate have largely moved uniformly to free-floating barrels.