Dear Technoid,

I recently bought an Armsport O/U 12 Gauge. It comes with fixed chokes which are full and mod. I use it for clay shooting and want to take the chokes out a little for a wider pattern. The problem is that it has a Chrome bore , is there any way to open it up. I would like to do it myself, is there a certain stone to use or special tool for doing this?

Thank You,

Dave

Dear Dave,

Chrome bores have many advantages (cheaper to produce as they require less final polishing, rust resistant, easy to clean), but they also have one major disadvantage. The chokes in a chrome bore barrel are hard to alter with conventional tools. Many gun makers (Parker Repro comes to mind) chrome the entire bore, including the “gunmaker’s chokes” and then cut the chokes afterwards with a special tool. This leaves the majority of the barrel chromed, but the choke areas clear of chrome so that they can be opened up later by the owner if he wishes. Other gunmakers cut or swage the chokes into the barrel before chroming so the chokes come chromed. This is what your Armsport gun has.

Chrome chokes do indeed require special tools and extra time to rework. I have cut some forcing cones in chrome lined barrels and the job required a carbide reamer. I really wouldn’t want to try to use the old brake hone on chrome chokes. Take it to a gunsmith for this one.

Best regards,

Bruce Buck
Shotgun Report’s Technoid
(Often in error, never in doubt.)