Maximize precision and control in your chambering work with the Reamer Handle EXR12 – Clymer 12" Rifle Extension. Built for professional gunsmiths who demand rock-solid feel and repeatable results, this premium reamer handle gives you the extra length, leverage, and stability you need when using Clymer or compatible chamber and throating reamers on rifle barrels. Brownells UK+2Brownells Deutschland+2
Professional-Grade Reamer Handle for Rifle Chambering
The EXR12 Reamer Handle (also listed as Clymer 12" Rifle Extension, Mfr. No. EXR12) is specifically designed as a barrel and chambering accessory for serious gunsmithing work. Brownells and Clymer describe it as a precision tool for the professional gunsmith, engineered to deliver rigid support and accurate alignment through the full length of the reaming operation. Brownells UK+2Brownells Deutschland+2
Whether you’re finish-reaming a new barrel or fine-tuning a custom chamber, the EXR12 is made to hold the reamer securely and transmit smooth, controlled torque.
Built from M-7 High-Speed Steel for Lifetime Service
Unlike generic handles or improvised extensions, the EXR12 is manufactured from high-quality M-7 High-Speed Steel, a material chosen for its toughness, hardness, and resistance to wear. Multiple Clymer/Brownells listings emphasize:
“Finest workmanship & quality; made in USA from M-7 High Speed Steel… These are precision tools for the professional gunsmith and will give a lifetime of service when properly cared for. Fully guaranteed.” Brownells France+3Brownells UK+3Brownells Deutschland+3
Key material advantages:
High strength under load – ideal for steady, controlled hand reaming
Excellent wear resistance – stands up to repeated use with steel reamers
Dimensional stability – maintains fit and alignment over time
This isn’t a disposable accessory; it’s a long-term shop tool designed to be part of your core gunsmithing kit.
12" Rifle Extension for Extra Reach & Leverage
As the name suggests, the EXR12 provides a full 12 inches of extension, giving you additional reach into the action and barrel without sacrificing control. Brownells UK+2Brownells Finland+2
That added length is especially helpful when:
Working on long-action rifles or deep chambers
Needing more clearance around the receiver and vise
Wanting greater leverage and finer torque control during finish cuts
By moving your hands farther back from the chamber mouth, the extension also helps keep your grip out of chips and cutting oil, making the process cleaner and more controlled.
Secure, Precise Fit with Clymer Reamers
The EXR12 is part of Clymer’s established line of barrel and chambering accessories, engineered to interface correctly with their chamber and throating reamers. Brownells notes that a customer used it to hand-ream a .35 Whelen chamber and reported “no play at all” between the handle and reamer, confirming the snug, precise fit. Brownells UK+1
Benefits of that tight coupling include:
Improved alignment between reamer and bore
Reduced risk of chatter due to sloppy connections
A more consistent, repeatable feel as you cut
When you’re chasing thousandths in headspace and finish, that level of precision in your tooling matters.
Made in the USA & Fully Guaranteed
Clymer has been supplying gunsmithing tools to the firearm industry since the 1950s, and multiple regional Brownells sites highlight that the Reamer Handle EXR12 is made in the USA and fully guaranteed. Brownells Europe+3Brownells Österreich+3Brownells Finland+3
What that means for your shop:
You’re working with a known, trusted brand in chambering tools
You get a tool that’s been field-tested by professional gunsmiths around the world
With proper care, it is designed to provide lifetime service
For anyone investing in a serious chambering setup, that kind of long-term reliability is a key selling point.
Gunsmith-Friendly Design & Shop-Ready Dimensions
Brownells’ technical data for the EXR12 lists the handle as a 12" rifle extension with a delivery weight around 0.454 kg (about 1 lb) and shipping dimensions of roughly 320 mm length x 10 mm width x 5 mm height. Brownells UK+2Brownells Deutschland+2
In practical terms, that translates to:
A slim, rigid profile that’s easy to maneuver around barreled actions and fixtures
Enough mass to feel solid in the hand without becoming unwieldy
A form factor that stores easily in a drawer, toolbox, or on a pegboard with your reamers
The handle is designed to be simple, strong, and purpose-built—no unnecessary bulk, just the extension and rigidity you need.
Ideal for Professional & Serious Hobby Gunsmiths
The Reamer Handle EXR12 is a smart choice if you:
Regularly perform barrel chambering, throating, or finish reaming
Want a dedicated extension handle instead of relying on improvised adapters
Prefer U.S.-made, fully guaranteed tools backed by a long-standing manufacturer Brownells Österreich+2Brownells Finland+2
From custom builds and caliber conversions to routine chamber touch-ups, the EXR12 is built to be the extension you reach for whenever precision and control are critical.
Key Features – Reamer Handle EXR12 (Clymer 12" Rifle Extension)
Summarizing the core specs from Clymer / Brownells listings: Brownells Schweiz+3Brownells UK+3Brownells Deutschland+3
Product Name: Reamer Handle – 12" Rifle Extension
Manufacturer: Clymer
Manufacturer Part Number: EXR12
Category: Barrel & chambering accessories / reamer handle
Material: M-7 High-Speed Steel
Length: 12" extension
Construction: Precision tool for professional gunsmiths
Origin: Made in USA
Durability: Designed to give lifetime service with proper care
Guarantee: Fully guaranteed by Clymer
If you’re looking to upgrade your chambering setup with a rigid, USA-made, M-7 steel reamer handle, the EXR12 Clymer 12" Rifle Extension is a proven, professional-grade choice for any serious gunsmithing bench.
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