BRM's Flexible Honing, Surface Finishing, and Deburring Blog Blog

BRM's Flexible Honing, Surface Finishing, and Deburring Blog

BRM's Flexible Honing, Surface Finishing, and Deburring Blog is the place for conversation and discussion about how to solve difficult finishing problems. For over 50 years, Brush Research Manufacturing (BRM) has helped customers use brushing technology to clean, rebuild, and resurface components ranging from engine cylinders to brake rotors to flywheels to firearms. BRM's Blog on CR4 provides real-world examples of how flex hones and wire brushes work. It also evaluates related technologies and invites questions from the community.

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Flexible Honing for XCR-L Rifle Chambers

Posted February 04, 2013 8:31 PM by Brush Research

The XCR-L rifle is a lightweight, heavy-duty firearm that's designed specifically for military, security, and law enforcement personnel. Made by the Robinson Armament Company, this modular weapon is also a favorite of firearms enthusiasts because of its ergonomic design and overall reliability. Like any long gun or pistol, however, a tight chamber can turn a day at the shooting range into an exercise in frustration.

Bad Ammunition and Failures to Eject (FTE)

For a user named "Kansas", a newbie at an on-line community called XCR Forum, his XCR-L worked well with most types of ammunition. A "strict diet of brass" kept the weapon well-fed, but then Kansas tried something new. On his way to the shooting range, he stopped at a gun store and bought some steel-cased ammo made by a different manufacturer. This sale-priced ammo caused a failure to eject (FTE) on the day's first shot. Even after adjusting the gas setting on his gun to 4, Kansas still struggled with FTEs.

Metal Casings and Coating Materials

To rule out a bad box of ammo, Kansas loaded another gun and unloaded the entire magazine without problems. The self-described "plinker" then measured the cases on brass PMC (9.2964 mm) and on his new steel-cased ammo (9.398 mm). Dimensions and metals aren't the only differences between ammo types, however. Coatings on casings also count. If a gun's chamber has even small surface irregularities, polymer-coated ammo with low lubricity may prevent smooth firing.

Surface Finishing is the Solution

Kansas had firearms questions, so he asked XCR Forum for answers. If he didn't have a bad box of steel-cased ammo, was the polymer coating the source of his problems? Or was a tight chamber alone the cause of multiple FTEs? His XCR-L had worked well for over six months, and he'd chambered about 1000 rounds before having problems with failures to eject.

"You have a tight chamber," explained a forum guru named Sean K. "Buy a Flex-Hone," the expert then advised, recommending the 400-grit silicon carbide (SC) Flex-Hone for Rifles from Brush Research Manufacturing (BRM). "That should cure your problem completely", the gun guru added, explaining how flexible honing corrects surface irregularities in gun and rifle chambers.

Flexible Honing for Firearms

Built with a stiff metal stem and flexible nylon filaments, BRM's Flex-Hone for Firearms produces the optimum surface finish in any type or size rifle chamber. These Made in the U.S.A. rifle brushes use a low-temperature, low-abrading process to produce a long-wearing surface finish, ensuring that your rifle's chamber remains at the precise dimensions required.

Contact us for more information or click here to watch this instructional video about the Flex-Hone for Firearms.


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