 This minimizes the variance in possible mechanical pressure distortions of the barrel alignment, and allows vibration to occur at the natural frequency consistently and uniform shot-by-shot.Alternatives include using a stock manufactured from composite materials which do not deform as much under temperature 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 most precision rifle designs have largely adopted free-floating barrels.