How does social identity shape Protestant attitudes about guns in the United States? Numerous studies show that religion shapes attitudes about guns, but the role of Protestantism in forming those attitudes is undertheorized and undertested. We draw from the extensive literature on religion-as-identity and the burgeoning literature of gun-ownership-as-identity to test the theory about the role of Protestant religion in cultivating a gun identity. We argue that for many Protestants, gun ownership has taken on the characteristics of a distinctive social identity, but that there are clear differences between different types of Protestants—notably, evangelicals and mainliners—that render the expansive category of “Protestant” largely irrelevant as an explanatory variable. While that finding might seem straightforward to scholars of religion and politics, the broad categorical approach—that is, treating “Protestant” as explanatory—has proven surprisingly durable in studies of gun ownership and attitudes about gun control. The analysis uses a recent Pew survey with batteries of questions about gun identity, gun policy, and religion. While this research note does not fully test why this relationship between Protestantism and gun identity exists, we do show that the relationship not only exists but also affects gun policy attitudes.