20 ga. chokes?

[Bruce A Lyons]

Thanks for the help. Im using some Chinese digital calipers. Let me try again and make sure Ive got them centered.

[Bill Murphy]

Judging from dozens of 20 gauge Parkers I have measured, you are not using an accurate tool. No 20 gauge Parker has chokes like your left barrel measurement. You should measure bore and chokes with a proper bore micrometer. That said, I agree with the others who say you have a modified and full gun.