If a barrel has a twist described as one turn in fifteen inches, what is the twist rate in inches per complete turn?

If a barrel has a twist described as one turn in fifteen inches, what is the twist rate in inches per complete turn?

• A. Twelve inches
• B. Twenty inches
• C. Fifteen inches
• D. Thirty inches

Answer: (A)

Twist rate is the distance the rifling travels along the bore for each full 360-degree rotation. If the description is one turn in fifteen inches, that means the rifling completes one twist every 15 inches of barrel length. So the twist rate in inches per complete turn is 15 inches. The other numbers would correspond to different describe distances per turn (e.g., a faster twist would be shorter than 15 inches, a slower twist longer than 15 inches).

Twist rate is the distance the rifling travels along the bore for each full 360-degree rotation. If the description is one turn in fifteen inches, that means the rifling completes one twist every 15 inches of barrel length. So the twist rate in inches per complete turn is 15 inches. The other numbers would correspond to different describe distances per turn (e.g., a faster twist would be shorter than 15 inches, a slower twist longer than 15 inches).