Lyman Brass Smith Bushing for Case Trim Xpress #4 .300 AAC .17 Rem Fireball

The Lyman Brass Smith Bushing for Case Trim Xpress #4 in .300 AAC Blackout and .17 Remington Fireball is a precision reloading accessory engineered for handloaders who demand consistent case preparation. This bushing assembly integrates with the Lyman Case Trim Xpress system to center and support bottleneck rifle cases during the trimming process, eliminating the need for separate pilots while maintaining tight case alignment with the cutting head.

The spring-loaded design facilitates smooth, effortless cuts across both cartridge types, enabling production rates of approximately 15 cases per minute—a practical throughput for serious reloaders managing volume brass processing. The bushing's support geometry is calibrated specifically for .300 AAC and .17 Rem Fireball case bodies, ensuring proper concentricity between the case neck and the trim cutter. This dimensional precision directly translates to uniform case neck length, a critical variable for cartridge consistency and chamber fit during firing.

Reloaders specializing in precision rifle ammunition, tactical training loads, or competitive shooting rely on case trim bushings to maintain the tolerances required for reliable feeding and consistent velocity. The #4 bushing designation confirms compatibility with the Lyman Case Trim Xpress platform, allowing integration into an existing reloading workflow without requiring additional equipment. For handloaders processing multiple bottleneck calibers, maintaining separate bushings for each cartridge type eliminates setup delays and reduces the risk of cross-caliber errors during high-volume brass prep sessions.