fxe is correct. Many guns, both American and English, have skinny barrels from the factory. That doesn't make it right. It also doesn't make me want to buy one with those barrels. I own a ten gauge Sauer bird gun that weighs 6 pounds 4 ounces and its wall thickness is closer to 30 than it is to 20. I have no idea how they did it, but they did it. The Brits shave their barrels down, inside and out, and send them to the proof houses and they pass proof. That doesn't mean I would buy those butchered up guns. If I get a chance, I will measure a few 0 frame 20 and 28 gauge Parkers and see whether I agree with fxe. By the way, Joe is right. Looking at .020 on a micrometer or vernier caliper will scare you.
