What number Cutts choke tube for .20 Gauge?

[Willard427]

I'm trying to buy a full choke tube for a Cutts on a 20 Gauge that I have coming. All the old ads reference 12 GA only. Does anyone have the numbers listing for 20 GA?

 

[rookhawk]

The number of cuts is universal across all chokes. 4 marks means the same thing, 1 mark means the same thing.

What is different is the amount of thousandths of choke restriction required to achieve that pattern. If 12-bore equals nominal bore diameter of .729” then an IC is 0.010” Restriction. Whatever cut mark references IC is what it is.

20-bore is a smaller nominal bore obviously, and to create an IC pattern restriction of a 20-bore isn’t the same amount of thousandths of choke restriction. The cut mark On the end of the choke is universal for IC-M-F, but the math to achieve that isn’t the same across gauges. Don’t quote me, but I think IC on a 20-bore is around .007”. There are charts on the internet for choke restriction.

TLDR; cut marks on chokes are universal across gauges.

 

[BeeMaa]

The number of cuts is universal across all chokes. 4 marks means the same thing, 1 mark means the same thing.

What is different is the amount of thousandths of choke restriction required to achieve that pattern. If 12-bore equals nominal bore diameter of .729” then an IC is 0.010” Restriction. Whatever cut mark references IC is what it is.

20-bore is a smaller nominal bore obviously, and to create an IC pattern restriction of a 20-bore isn’t the same amount of thousandths of choke restriction. The cut mark On the end of the choke is universal for IC-M-F, but the math to achieve that isn’t the same across gauges. Don’t quote me, but I think IC on a 20-bore is around .007”. There are charts on the internet for choke restriction.

TLDR; cut marks on chokes are universal across gauges.

To add to this, each manufacturer has their own idea of what constriction is best. This means that a Beretta FULL choke could be the same diameter as a Benelli IM choke. Best to get the information from the maker. What brand of shotgun are you getting?