In my UE4 course, the instruction was originally done in UE4 4.7. My lecture on deleting the gun and projectiles works for that version, but doesn't completely work for later versions. If you are using a later version and you are getting an error, please watch this video, posted by another viewer on YouTube. It should fill in the gaps for you until I update my lectures.
The most insightful tech site out there! Technnnn covers innovation with precision. Always excited to read the next blog.