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gjgalligan
01-08-2006, 12:09 PM
I was wondering how to properly measure a barrel.
At the moment I am interested with the shotgun barrel measurement as I have an old shotgun that I am thinking about cutting down.
Does the 18" include the chamber (area that the shell rest when ready to fire)?

Also, If I cut the barrel down do I have to put a front bead/sight on it?

Thanks for any help.

enfield
01-08-2006, 02:28 PM
It's my understanding that the barrel length is from end to end, including the chamber. I'm not aware of any requirement anywhere that a barrel or gun has to have sights on it.

Knimrod
01-08-2006, 02:58 PM
Barrel measurements are made from the breech face to the the muzzle. The easiest way is to simply insert a cleaning rod in the muzzle until the end of the cleaning rod contacts the breech face (or closed bolt face), mark the rod at the muzzle face or end of the muzzle attachment (muzzle brake, flash suppressor, choke, etc.), then measure the distance from the tip of cleaning rod to the mark.

Brian
01-08-2006, 04:22 PM
As a rule you should/may want to consider adding a half inch to your measurement for a little extra insurance. It's good to have extra for cleaning up the muzzle of tooling marks, this way you wont sand or grind away any length needed for the "legal" measurement.

Front sight is optional at this point but if you add one be sure to clean up anything that sticks into the I.D. of the barrel, file and drum sander or sand paper wrapped around a dowel and spun in a drill work well.

Dale
01-09-2006, 10:14 AM
Barrel measurements are made from the breech face to the the muzzle. The easiest way is to simply insert a cleaning rod in the muzzle until the end of the cleaning rod contacts the breech face (or closed bolt face), mark the rod at the muzzle face or end of the muzzle attachment (muzzle brake, flash suppressor, choke, etc.), then measure the distance from the tip of cleaning rod to the mark.


The muzzle brake, flash supressor, whatever, must be permanently attached not just screw on. The extra half inch (Brian's idea) never hurts either.

gjgalligan
01-09-2006, 08:22 PM
Barrel measurements are made from the breech face to the the muzzle. The easiest way is to simply insert a cleaning rod in the muzzle until the end of the cleaning rod contacts the breech face (or closed bolt face), mark the rod at the muzzle face or end of the muzzle attachment (muzzle brake, flash suppressor, choke, etc.), then measure the distance from the tip of cleaning rod to the mark.


I had thought of this but it just seemed so easy that it couldn't be right.

Thanks everybody!:)

banjobart
01-26-2006, 12:01 PM
I cut down my 870 Synthetic from 28" to 18.5 inches. The barrel had a rib so I drilled and tapped it for a fiber optic front sight. You can buy the tap from Brownells or the local hardware for a buck or two. It looks great, I did touch up blue on the muzzle. No one would ever guess it is not a stock 870 Police or Home Defense model. I also installed a Tac-Star mag extension so it holds eight.

One can also drill and tap the barrel for a bead sight if there is no rib. The screw in beads are available from Brownells. Use locktite or solder to hold them tight.

The resulting cylinder choke will work fine with today's modern shot cups and cushioned wads. It will also shoot buckshot and slugs like a dream.

gjgalligan
01-28-2006, 08:08 PM
Let me go a step further:
I have an older Sear's Brand auto loader with the twist type adj choke on it.
Any reasons why I can't or shouldn't cut this one off?
One paerson said that the auto load would not work right if I cut it off. I think he is crazy. I can't see any difference.

goldwing2000
01-28-2006, 09:40 PM
If it's gas operated, you would lose the autoloading function if you cut too close to the gas port.

If it's recoil operated, I can't see how it would be affected.

Brian
01-29-2006, 12:45 PM
As long as you don't cut back far enough to remove the gas port going from the barrel to the "gas chamber" it should work, might even get a little sluggish if you get to close, the gas needs time to do its thing before the shot leaves the barrel. What model is it?