These pictures are of the SmartStocktm Accuracy Tuner System shown incorporated into a Bell and Carlson Medalist rifle stock.
The Medalist Stock Inletted For SmartStock Accuracy Tuner.
Completed Medalist SmartStock with tuner installed.
Small hole in stock forend for screwdriver adjustment of tuner.
Underside of SmartStock, showing the two barrel taper adjustment allen screw access holes.
The barrel taper adjustment is set to match the change in barrel diameter, so that when the tuner is moved along it's full length of travel, the pressure of the Delrin block against the barrel remains constant. This is necessary on a tapered barrel to eliminate ramping of the barrel, up or down, as the tuner is adjusted. It only needs to be adjusted once (when the action is first mounted into the SmartStock) to match the rifle barrel taper.
SmartStock Tuner Operation
The concave Delrin block of the tuner contacts the barrel with a specific set pressure. As the tuner adjustment is turned it moves the block either forward or backward along the bottom of the barrel, locking the block in place every one half turn. Each half turn changes the effective length of the forward end of the free floated barrel 1/64 of an inch. This changes the harmonic vibrational frequency of the barrel oscillations. This both dampens the amplitude of movement, and allows null point adjustment of the barrel oscillations to be obtained at the instant the bullet leaves the muzzle. This change in effective barrel length allows the shooter to adjust the impact of the projectiles into to the smallest group size possible with any given load.
U.S. Patent #5423145