Gain Twist Rifling

 

    Gain twist rifling can offer advantages over conventional twist rifling. First let us describe gain twist. Gain twist is when a gun barrels rifling, starting at the breech end of the barrel is a given rate of twist, say 1-96 which translates into 1 turn in 96 inches. As we move forward towards the muzzle this twist evenly increases to say 1-48, again translating to 1 turn in 48 inches. Gain twist is derived from the forming of a parabolic curve.

Now, the advantages of gain twist rifling. For the person that wants to shoot only round balls through their black powder rifle you will not be handicapped, if fact you can realize greater accuracy potential and power. As the ball travels through the bore the increased resistance from the increasing rifling twist will allow for a longer and more even pressure curve. If we think of it this way, black powder or black powder substitutes burn the entire length of the barrel. If fact you can load too much powder and literally blow unburnt powder out of the bore. This is why muzzleloaders have such long barrels, to allow the powder to be fully consumed in the barrel and not on the ground. Gain twist rifle barrels help take advantage of the long powder burn time.

If you want to be able to shoot both round balls and saboted bullets you will indeed have advantages. The faster twist will allow for the stabilization of these longer bullets, giving the person that would like to hunt with a more traditional rifle the option to use more modern bullets.

Our gain twist is set at 1-96” to 1-48” in a 42” length. That does not mean that we cannot rifle longer or shorter lengths. In longer lengths the twist at the breech will be slightly less. Shorter lengths will be slightly more. The muzzle always stays constant. Also, the rate of twist as a whole can be increased or decreased, allowing a faster twist at the muzzle or a slower twist.

 

   Gain twist rifling is an old concept that is not offered much anymore due to the fact that it is much more difficult to machine. The extra cost for gain twist rifling will provide a much more versatile muzzleloading rifle.

 

 

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