RCBS Case Trimmer Collet #3 - Precision Reloading Tool for Accurate Case Trimming

The RCBS Case Trimmer Collet #3 is a precision case-holding accessory built for reloaders who demand consistency in cartridge preparation. If you're trimming rifle or pistol brass to exact specifications, this collet clamps cases securely in place using a draw-collet design similar to what you'd find on a lathe—ensuring repeatable, straight trimming without runout. It's a straightforward but critical piece of the case prep workflow that directly impacts ammunition quality and firearm reliability.

Collets are case-specific: each number corresponds to a range of cartridge diameters, so the #3 fits certain case types while others require different collets. RCBS publishes a detailed compatibility chart to help you match the right collet to your cartridges. If you're reloading multiple calibers, you may need more than one collet. The #3 works with RCBS trimmer platforms, including the Trim Pro Manual Case Trimmer and Trim Pro-2 Power Case Trimmer (both sold separately), and requires a case trimmer pilot as well.

This is foundational reloading equipment—not flashy, but essential. Whether you're a handloader building precision rifle ammunition for the range or producing consistent pistol rounds, proper case trimming prevents feeding issues, maintains chamber fit, and keeps your brass in shape for multiple reloads. The collet system is a proven design that's been a standard in reloading benches for decades.

Key Features

• Draw-collet design secures cases for accurate, straight trimming
• Fits a range of cartridge case diameters within the #3 specification
• Compatible with RCBS Trim Pro Manual and Trim Pro-2 Power Case Trimmers
• Sold separately; requires a compatible case trimmer and pilot

Specifications

Frequently Asked Questions

What cases does the RCBS #3 collet fit?

The #3 collet accommodates a range of cartridge case diameters. RCBS publishes a trimmer collet compatibility chart detailing which specific cartridges work with each collet number; consult that chart to confirm fit for your calibers before ordering.

What equipment do I need to use this collet?

The Case Trimmer Collet #3 works with RCBS case trimmer platforms. You'll also need a case trimmer pilot and a trimmer body—specifically the Trim Pro Manual Case Trimmer or the Trim Pro-2 Power Case Trimmer. These are sold separately.

Can I use one collet for multiple calibers?

No. Each collet number is designed for specific case diameters. If you reload multiple cartridges of different diameters, you'll need to purchase additional collets that match each caliber group.

Is this a complete case trimmer system?

No. The collet is one component of the trimming system. You'll need to pair it with a compatible RCBS case trimmer body, a trimmer pilot, and a cutter head to create a complete setup.