4. Magazine Loader 
You could spend a lot of time and energy loading a magazine in less than ideal conditions or you could utilize a magazine loader to save your thumbs.
Yes, everyone needs to know how to quickly and properly load a magazine without assistance. However, as long as you practice your skills from time to time, there’s nothing wrong with making life easier when you’re taking target practice.
Speaking of which, you do have extra magazines for your favorite guns, right?