No idea about the context, but you can easily fix your problem if you just set the property’s value manually instead of using the tools (e.g. making it 166.1 instead of 166.16).
This also appears to only be affecting a single part, which should be a fairly accurate sign that it’s not a Roblox issue. If you need to ask if it’s a bug, don’t post it as a bug report and instead post it somewhere else (such as #development-support:building-support).
This is one clickbaity title. Not really relevant anymore since this was posted nearly 2 months ago, but it’s just your increments. You can use other increments, plugins or command bar code if these kinds of things happen.