Gun ownership for green card holders in new york?

Federal law prohibits a green card holder to buy any gun. NY penal code has nothing to do with it. It's possible you might be able to pass a background check since they may only check for criminal records. Still it would be illegal, but maybe your dealer doesn't care about that. It wouldn't be the first or last corrupt firearm dealer. It just so happens that in NY no one can buy a pistol with out a permit, so they all can only buy rifles or shotguns in NY.