How do I determine the choke?

[Sebastian the Ibis]

I bought a used 28inch barrel for my Mossberg 500 12 ga. There is a choke in it, it looks like there is no taper but I can't tell for sure.

How can I determine what type of choke is in there cylinder, IC, modified etc. and how do I know if it is safe to shoot slugs through it?

Thanks.

 

[Mojo-jo-jo]

Cylinder bore diameter for 12 gauge = .729 inches

Get out your dial caliper and see chart 2 on this page: http://www.wildfowlmag.com/tips_strategies/shotgun_062304/

 

[dirty dave]

Brownells sells a cheap choke gauge ,reads all gauges.for a 12gauge if you can drop a dime in barrel and it passes through its ok for slugs.

 

[DaleCooper51]

If it is a fixed choke barrel, it should be marked near the end that goes into the receiver. If it is not marked, either measure it with a gauge or caliper.

You could also go to the patterning board and shoot it to see how it does.

 

[oneounceload]

If there is a removable choke tube in it, take it out and read what is laser-etched on the side of it. If there is no choke, and the barrel has not been Bubba'd, it will state what the constriction is supposed to be near the receiver. I say "supposed to be", because what it says and how it patterns is not always in sync. Take it to a pattern board with the ammo you are going ti use in it and see what it does. There are numerous places that describe how to pattern a shotgun properly. Unless you can measure the bore diameter as well as the muzzle, you may or may not get the true constriction of the barrel