Button Rifling has been in development since the end of the 19th century but wasn’t really perfected until the 1940s by employees of Remington Corporation. Button Rifling is the most common method of manufacturing rifled barrels in the United States today. Button Rifling machines are used for making helical grooves in the barrel of a firearm or gun, which produces a spin to a projectile around its long axis. This spin serves to gyroscopically stabilize the projectile, improving its aerodynamic stability and accuracy.
Rifling is often described by its twist rate, which indicates the distance the rifling takes to complete one full revolution, such as “1 turn in 10 inches” (1:10 inches), or “1 turn in 254 mm” (1:254 mm). A shorter distance indicates a “faster” twist, meaning that for a given velocity the projectile will be rotating at a higher spin rate.
Button rifling is very common among most barrel makers in the United States. In fact, it is the most used method today, because of the small amount of time needed to make the rifling, and the fact that if the barrel-maker is experienced, the dimensions of the final product can be very accurate as well.
Cut Rifling, also known as Single Point Cut Rifling, is one of the oldest methods of rifling and dates back to the time that rifling was first invented in Nuremberg, Germany in 1520. Cut Rifling consists of removing steel from the inside of a barrel using a cutting tool with a hard point. The cutting tool used is called a “hook cutter”.
The cutting tool is attached to a cutter box, which contains a mechanism to raise the cutter. The cutter box is cylindrical in shape and is made smaller than the bore of the barrel, so that it may be inserted into the barrel. The other end of the cutter box is attached to a hollow steel tube through which coolant fluid is pumped to keep the cutting head cool. As the cutter box is pulled through the barrel, it is also rotated about its axis at a set rate to give the rifling a spiral shaped groove.
The hook cutter mounted into a cutter box. The hook cutter is in the middle of the cutter box and the sharp edge is exposed via the groove in the cutter box. The hook cutter sits on a wedge and when the thin screw at the end of the cutter box is turned, it pushes the wedge forward under the cutter, thereby raising the cutter outwards to increase the depth of the cut.