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

The Lyman Brass Smith Case Trim Xpress Bushing #4 is a precision case-trimming accessory sized specifically for 300 AAC Blackout and 17 Rem Fireball cartridges. If you're loading these rounds, consistent case length is non-negotiable for reliable feeding and safety—and this bushing eliminates the guesswork and tedious setup that comes with traditional trimming methods. It's part of Lyman's Case Trim Xpress system, designed to make brass prep faster and more consistent without fiddling with pilots or complex alignment.

The spring-loaded design keeps steady pressure on the case as it moves across the carbide cutter, producing a clean, square trim cut every time. Because the bushing itself guides and supports the case, you're not wrestling with separate pilots or worrying about casing tilt—just push the brass through and let the tool do the work. That means less hand fatigue and fewer malformed case mouths when you're running volume.

Whether you're prepping once-fired brass or managing a growing stockpile of reloads, a dedicated bushing for your specific cartridge keeps your process streamlined. The carbide cutter handles brass efficiently without dulling, so you'll get consistent performance across dozens of trims.

Key Features

• Spring-loaded design for smooth, consistent case trimming
• Carbide cutter built into the Case Trim Xpress system
• No separate pilots required—bushing supports the case directly
• Sized specifically for 300 AAC Blackout and 17 Rem Fireball
• Produces clean, square case mouth cuts

Specifications

Frequently Asked Questions

What cartridges does this bushing trim?

This bushing is sized for 300 AAC Blackout and 17 Rem Fireball. Each Lyman bushing is caliber-specific, so verify the #4 designation matches your rounds before purchasing.

Do I need separate pilots to use this bushing?

No. The Lyman Case Trim Xpress Bushing #4 supports the case directly with its spring-loaded design, eliminating the need for traditional pilots. The bushing itself guides the brass against the carbide cutter.

Is this bushing compatible with other case trimming systems?

This bushing is designed as part of the Lyman Case Trim Xpress system. Compatibility with other trimming equipment should be verified before use.

What type of cutter does it use?

The bushing works with a carbide cutter that's part of the Case Trim Xpress system. Carbide maintains its edge through consistent use across many trims.