Restore worn 20-gauge chambers with confidence using the Clymer Shotgun Rim Cutter & Headspace Ring – RC20GA. Engineered specifically for 20 gauge shotguns, this precision tool set lets professional gunsmiths and serious hobbyists recut damaged rim recesses and restore proper headspace on older or heavily used guns. Brownells+2Brownells UK+2
Designed and manufactured by Clymer, a trusted name in chambering tools, the RC20GA Rim Cutter 55° Fits 20 Gauge is built to deliver clean, accurate cuts and long service life on the bench. Brownells UK+3Brownells+3Brownells Italia+3
What the Clymer Shotgun Rim Cutter & Headspace Ring RC20GA Does
Over time, repeated firing and years of use can erode or peen the rim-recess area of a shotgun chamber. That damage can cause:
The Clymer Shotgun Rim Cutter & Headspace Ring RC20GA is specifically designed to remove the damaged metal and rebuild the rim seat: Brownells Sverige+3Brownells UK+3Brownells France+3
Solder the steel headspace ring into the worn chamber. Brownells Sverige+3Primary Tactical+3Pacific Tool & Gauge+3
Use the 55° rim cutter to recut the chamber rim to the correct depth and profile. Primary Tactical+3Brownells Italia+3Brownells Sverige+3
The result: restored, correct headspace and a clean, uniform rim recess in your 20 gauge chamber. Brownells Sverige+3Brownells UK+3Brownells France+3
Purpose-Built for 20 Gauge Shotguns
The RC20GA version is dimensioned for 20 gauge only, ensuring proper alignment and geometry in 20 ga chambers: Brownells Schweiz+3Brownells+3Brownells UK+3
Cartridge: 20 Gauge
Style: Chamber rim cutter with matching headspace ring
Application: Shotgun chambers with worn or damaged rim-recess areas, especially in older or high-mileage 20 ga guns
If you routinely service 20 gauge field guns, classics, or family heirlooms, this tool set is a key addition to your reamer and cutter drawer.
M-7 High Speed Steel Cutter – Built for a Lifetime of Use
Clymer’s rim cutter is made from M-7 high-speed steel, the same tool steel used for premium chamber reamers and cutters. Product descriptions emphasize this material for its durability and professional-grade performance. Primary Tactical+2Brownells Österreich+2
Cutter Features:
Material: M-7 high-speed steel
Profile: 55° rim cutter optimized for 20 gauge chamber rims Brownells Österreich+1
Use: Recuts the rim seat after the headspace ring is soldered in place
M-7 HSS delivers:
For best results, follow standard practice with quality petroleum-based cutting lubricant, as recommended for shotgun rim cutters in similar applications. Pacific Tool & Gauge+1
Steel Headspace Ring – Rebuild & Reset the Rim Recess
The headspace ring works together with the cutter to rebuild the chamber’s rim seat:
20 gauge headspace ring dimensions (from comparable 20 ga headspace rings) are typically around:
Inside diameter sized for 20 ga hull body
Outside diameter matched to 20 ga chamber
Approx. ¼" long steel ring designed to be soldered and then recut Pacific Tool & Gauge+1
Once installed and recut, the ring effectively restores the rim seat instead of scrapping or sleeving the entire barrel.
Restore Headspace on Worn 20 Gauge Guns
Clymer and Brownells repeatedly describe this system as an “essential tool for restoring headspace on worn guns” and for removing damaged metal from shotgun chambers. Brownells Sverige+3Brownells UK+3Brownells France+3
Typical uses include:
Bringing older 20 gauge pumps and doubles back into safe service
Correcting stretched or battered rim recesses from heavy use or high-pressure loads
Extending the life of classic or discontinued 20 ga shotguns where replacement barrels are costly or unavailable
Because headspace directly affects safety, reliability, and case life, this tool set is especially valuable in professional gunsmithing environments where proper chamber dimensions are non-negotiable.
Made in the USA – Professional Gunsmith’s Choice
The Clymer Shotgun Rim Cutter & Headspace Ring RC20GA is listed as Made in USA and built as a precision tool for gunsmiths. Brownells Österreich+2Brownells Sverige+2
Why shops rely on tools like the RC20GA:
Backed by Clymer’s long-standing reputation in chambering and reamer tools
Built to professional tolerances for consistent results
Intended to provide years of service with proper storage, cleaning, and lubrication
If you’re outfitting a full-service shotgun bench, this is a go-to solution for 20 gauge headspace correction.
Product Specs – Shotgun Rim Cutter & Headspace Ring RC20GA
From Clymer and major distributors: Brownells Schweiz+5Brownells+5yellowstone-armory.com+5
Product Name: Shotgun Rim Cutter & Headspace Ring – Rim Cutter 55° Fits 20 Gauge
Brand / Manufacturer: Clymer
Manufacturer Part Number: RC20GA
Brownells Product No.: 184115020
Cartridge: 20 Gauge
Style: Chamber Rim Cutter with matching headspace ring
Cutter Material: M-7 high-speed steel
Headspace Ring Material: Steel, designed to be soldered into chamber, then recut
Purpose: Remove damaged metal from rim recess and restore correct headspace on worn 20 ga shotguns
Delivery Weight: Approx. 0.204 kg (about 0.45 lb) Brownells Österreich+1
Category: Gunsmithing tools / Bore & barrel tools / Reamers & cutters
If you need a professional-grade solution to repair worn 20 gauge chambers and bring headspace back into spec, the Clymer Shotgun Rim Cutter & Headspace Ring RC20GA is a proven, shop-ready tool set that belongs in every serious shotgun gunsmith’s arsenal.
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