Barrel Harmonics

The sporter-weight barrel often describes a figure-8 or eliptical movement at the muzzle.

Q: In articles I’ve often seen mention of “barrel” harmonics, but they never seem to explain what they are? Can you please explain exactly what kind of a tune the barrel plays?
Scott Harrison

A: Of the many forces that affect accuracy, barrel vibration is probably foremost. When a gun is fired, the barrel whips about. This vibration, or barrel harmonic causes the muzzle to describe an arc, and at some point along

Choosing a barrel vibration node with minimal movement will give better on-target consistency.

that arc, the bullet exits the muzzle, Dwell time, then, would affect where along that arc, the bullet leaves the muzzle, resulting in the different points of impact for identical loads. Barrel bedding,fore-end tip pressure points, and free floating are methods used to gain optimum accuracy by dampening these vibrations to get the bullet to leave the muzzle at exactly the same point in the arc every firing.

Nick Harvey

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The late Nick Harvey (1931-2024) was one of the world's most experienced and knowledgeable gun writers, a true legend of the business. He wrote about firearms and hunting for about 70 years, published many books and uncounted articles, and travelled the world to hunt and shoot. His reloading manuals are highly sought after, and his knowledge of the subject was unmatched. He was Sporting Shooter's Technical Editor for almost 50 years. His work lives on here as part of his legacy to us all.