0.339'' Breech Lock Bullet Sizer & Punch

The Lee Precision 0.339'' Breech Lock Bullet Sizer & Punch is an essential reloading tool designed for precision handloaders and competitive shooters who demand consistency in ammunition preparation. This specialized sizing die works with the Breech Lock system, allowing shooters to produce uniformly sized bullets that promote reliable feeding, accurate grouping, and extended barrel life. Whether you're preparing match-grade ammunition or optimizing factory rounds for your specific firearm, this tool delivers the precision control that serious reloaders require.

This 0.339'' sizer and punch utilize Lee Precision's proven Breech Lock design, which provides fast, tool-free caliber changes and repeatable alignment with minimal setup time. The punch component removes sizing expander balls or performs secondary operations, while the sizer body ensures bullets meet precise diameter specifications for your chosen caliber. The compact form factor—weighing just 0.13 lbs—makes it an efficient addition to any progressive or single-stage press setup, and the durable construction ensures accurate performance through thousands of reloading cycles without wear or drift.

Handloaders working with .338-caliber rifles, such as the .338 Lapua Magnum, .338 Federal, or similar cartridges, will benefit most from this precision tool. It integrates seamlessly with any Lee Precision Breech Lock compatible press, making it an ideal upgrade for shooters expanding their reloading capability or transitioning to a new caliber. Proper use of this sizer ensures bullet runout stays minimal, chamber pressures remain consistent, and velocity spreads tighten—all factors that directly improve accuracy at distance and reduce shooter-induced variables in your ammunition quality.