Subjectivity in bullet casing matching method is not based on scientific proof. Bitemark opinions are no better.

An Oregon appeals court found that the AFTE gun forensics method in cases involving shootings is not “scientifically valid” and could change how these cases are prosecuted in the state.
— Read on www.koin.com/news/oregon/oregon-appeals-court-finds-gun-forensics-method-is-not-scientifically-valid/