Also known as last bullet.

This mod will prevent shooting the last round of your magazine for certain guns, enabling you do perform a faster tactical reload than with an empty mag. You can configure which categories of guns this applies to via mod options.

Thanks to my pal Minga for the idea.

Update:
Fixed the animation issue and enabled reloading automatically when on the last bullet. Additionally, it won't prevent you from shooting your very last bullet if you're on your last mag.