Ball Hones for Shotgun Forcing Cones

Shotgun forcing cones are tapered sections between the chamber and the bore. By forcing the shot charge or column through a narrower area, chamber-to-bore forcing cones increase pattern density. Although shotgun forcing cones vary in length, longer is generally better. Shooters disagree about the ideal length, but longer forcing cones reduce recoil and increase shot velocity. Because the transition within the shotgun barrel is at a gentler angle, there’s also less deformation of the shot pellets.  

Forcing Cone Reamers and Flexible Honing Tools

Rifleshooter.com is a website with news, reviews, and do-it-yourself (DIY) tips for shooters and hunters who want to learn more about rifles, shotguns, pistols, and ammunition. Recently, a post called Lengthening a Shotgun Forcing Cone explained how to improve shotgun performance. First, apply a liberal coat of cutting oil to a forcing cone reamer. Next, secure the barrel in a vise and insert the reamer into the breach. Turn the barrel carefully, removing metal shavings and reapplying oil as necessary.

Once the forcing cone is cut, it’s time to hone the metal surfaces. Rifleshooter.com recommends the Flex-Hone® tool, a ball hone made by Brush Research Manufacturing (BRM). All Flex-Hone® for Firearms tools quickly and easily produce the optimum surface finish. By using a low-temperature, low-pressure abrading process, BRM gun brushes also produce a long-wearing surface every time. These high-quality surface finishing tools also keeps shotgun bores at the precise dimensions required.

The Flex-Hone® for Shotguns

Brush Research provides three types of gun brushes for smoothbores: shotgun barrel hones, forcing cone hones, and chamber hones. Use shotgun forcing cone hones after removing metal from the bore with a reamer. The Flex-Hone® for Firearms is a surface finishing tool and not designed for heavy-duty material removal. For best results, use BRM forcing cone hones with Flex-Hone® oil, a blend of honing and lapping oils that includes a moisture-dispersant and a special additive that keeps metal shavings in suspension.     

How to Choose Shotgun Forcing Cones

BRM shotgun forcing cones are 10” long and feature a 1-5/8” silicon carbide (SC) abrasive. Depending on your smoothbore, choose a 12, 16 or 20 gauge (GA) cylinder honing tool. Finally, specify 180, 400, or 800-grit. Rifleman.com used a medium-grit flexible hone and then a fine-grit forcing cone hone. Because the Flex-Hone® for Firearms is built with a metal stem, BRM ball hones can be used with a handheld electric drill. Use the medium-grit hone first, clean the slurry from the barrel, and then use the fine-grit cylinder hone. Inspect the shotgun barrel’s surface every few strokes, and never over-hone.     

Have you used the Flex-Hone® for Firearms? What was your experience, and is your firearm now firing with less recoil and more shot velocity? Let BRM know by commenting on this blog entry.