Snapchat has mechanisms in place to safeguard the privacy of its users. When it comes to screen recording a Snap story, Snapchat may be able to detect it. This is because they want to ensure that the content shared within their app remains private as intended by the sender. For public stories, while the detection might not be as strict as for private ones, it's still possible. There are also technical ways that Snapchat could potentially use to identify screen recording activities, such as monitoring device functions related to screen capture. But it's not always 100% foolproof, and there may be some situations where it might not be detected, though these would be exceptions rather than the norm.
Well, Snapchat does try to prevent unauthorized screen recording. It can often detect when you're using certain built - in screen recording features on your device. However, there are some workarounds that people might try, but these are against the platform's terms of use. So, in general, there's a good chance that Snapchat can tell if you screen record a story, especially if it's a private or protected one.