What is the test for insufficient evidence to convict a BATF agent of possession of an assault rifle?

Appellant urges that the evidence was insufficient to show that the firearm was "in or affecting commerce." When reviewing the sufficiency of evidence to support a criminal conviction, "the relevant question is whether, after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found the essential elements of the crime beyond a reasonable doubt." Jackson v. Virginia, 99 S.Ct. 2781, 2789 (1979) (emphasis in original). Rational jurors could have concluded that even if the BATF agent's knowledge was spotty and the commercial sources he used inaccurate, still, the firearm was not made in Alaska and had to have travelled in interstate commerce to get to Alaska.