Anyone tell me what these choke No's mean?

[vega]

Hey Gentlemen, my new-to-me CZ (Brno) 16 gauge double has choke designations of 16.4 and 16.2. Anybody tell me what these mean in North American terms?

Thanks a lot.

 

[Claybuster]

Nominal 16 gauge bore is .662 inches or 16.8mm. Your constrictions are .2mm and .4mm which equals .008" and .016". IC/Mod for all intents and purposes.

 

[rembolt]

Could the chokes be numbered 1 through 5 .1 being full and 5 being cylinder which would make the chokes you have( imp mod) and (imp cyl).

 

[Ahsan Ahmed]

Nominal 16 gauge bore is .662 inches or 16.8mm. Your constrictions are .2mm and .4mm which equals .008" and .016". IC/Mod for all intents and purposes.

X2 per the stamps.

The only way to become sure of the actual constrictions at present would be to measure those at this point in time.

 

[vega]

Thank you all, very much. Greatly appreciated.