Lyman Outside Chamfer Tool

The Lyman Outside Chamfer Tool is a precision reloading instrument designed for shooters and ammunition manufacturers who demand consistent case preparation across multiple calibers. This compact deburring tool addresses a critical step in the cartridge finishing process—removing sharp edges from case mouths—that directly impacts bullet seating consistency, chamber fit, and overall round integrity. Whether you're loading for precision rifle competitions, tactical training, or duty ammunition, proper case mouth chamfering is non-negotiable for reliable chambering and accuracy.

Built with Lyman's engineering standards, the Outside Chamfer Tool features a compact 6.75-inch design that delivers even deburring action on the external case mouth from .17 caliber through .45 caliber cartridges. The tool works by removing microscopic burrs created during case trimming and resizing—burrs that can cause inconsistent bullet seating depth and prevent flush chamber contact. Its manual operation provides tactile feedback and user control, ensuring uniform chamfer geometry without over-cutting. This tool complements Lyman's VLD Inside Chamfer Tool, allowing reloaders to execute complete bidirectional case mouth preparation for match-grade ammunition.

Serious handloaders benefit most from this tool, particularly those working with tight-tolerance cases or shooting precision rifle platforms where case concentricity and seating consistency directly influence shot grouping. Law enforcement and military armorers managing bulk ammunition production rely on systematic case prep to maintain reliability and interchangeability. The wide caliber range—from rimfire (.17) to large pistol (.45)—makes it an economical single-tool solution for multi-caliber operations. Weighing just 0.13 pounds, it stores efficiently in any reloading bench setup and requires no special installation or equipment beyond standard manual operation.