Reiterating what others have said, unless you're a range rat shooting thousands of rounds, I don't think many reloaders are actually saving money. We reload because we enjoy the process and maximizing performance for a given bullet/gun.
I probably have the same 4k panasonic as you. Like you mentioned, it's very lightweight. Also has exceptional built in lens zoom. For anyone not shooting professional footage, I think it works great for capturing footage of animals.