Despite the fact that many people are unintentionally killed or injured in firearms-related incidents each year in the USA, there has been little research conducted on firearms safety. The current study addresses this issue with one possible explanation: some people may think that they are more competent with firearms than they are. Overconfidence may lead to unsafe behaviors and accidental firearm discharge. Therefore, one approach to addressing this problem is to examine the relationship between perceived and actual firearm competence. The hypothesis was examined by using a video-based test in which people viewed a person manipulating a firearm, then answered safety-related questions. Overconfidence was observed in the lowest quartile of performance for questions concerning the outcome of pulling the trigger. Once validated, the firearm functioning test could be made publicly available, allowing a wide audience to easily obtain an objective assessment of their firearm-safety competence