Barrel Failure in an Over and Under Shotgun

Stephen Batzer

doi:10.51501/jotnafe.v43i1.985

Authors

Stephen Batzer https://orcid.org/0009-0006-1173-8678

DOI:

https://doi.org/10.51501/jotnafe.v43i1.985

Keywords:

over-and-under shotgun, barrel rupture, factory ammunition, metallurgy, manufacturing defect, forensic engineering

Abstract

A 12-gauge over-and-under shotgun experienced a rupture in its lower barrel when firing standard factory ammunition. This incident marked the shotgun’s first use in the field, as it had only been test-fired at the factory with regular-pressure shells (not proof loads) prior to this event. The barrel steel split axially ahead of the reinforced chamber, under the polymer fore-end, causing hot gases and plastic debris to violently strike the shooter’s left hand, resulting in serious injury. A detailed metallurgical and geometric evaluation of the affected barrel was conducted at an independent third-party laboratory. Chemical analysis confirmed the steel matched SAE 1045 alloy with appropriate hardness for the barrel’s intended thickness. Performance testing on a new, identical shotgun using intentionally overloaded shells was also carried out, despite the spent hulls from the incident showing no signs of excessive pressure. The assessment uncovered a distinct manufacturing flaw in the lower barrel, creating a localized weak spot in the barrel wall.

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