Better Rifling calc How To Find the Ideal Twist Rate for Your Rifle Matching Rifle Twist Rate to Caliber bullets. Twist Rate Electroplating Etching

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A newer technology, Electrolytic Cationic Machining, uses a wet-etching method that uses reverse-electroplating to remove from inside the barrel rather than add to it. These machines utilize electrodes shaped as plastic cylinders with reverse-imaged metal strips encircling them. To create the desired twist rate, the cylinder is pushed through the barrel while the barrel is immersed in chemicals like sodium nitrate and methodically rotated. Although this is an expensive method of rifling, it results in precise rifling.