Read the title, moron. I'm not even sure I should write this. So, if you get killed, don't come cryin ta me...
All these gun-handlers, spinners and such, you see on TV and the movies, are fools if they have their guns loaded. I played at it, and got good, then realized the value of some of the moves, as well as it being a great way to shoot your own balls off by accident.
There may come a time when you have to pass your weapon from one hand to the other, for some reason or the other. Keeping in mind that this is a great place to disarm yourself, and thus be fucked, practice, practice, practice. And then practice some more.
And then practice some more.
Start off with a thick handled butter knife, and pass it from hand to hand. Learn to open the fingers of the weapon holding hand, and shoot the knife into the slightly cupped palm of your empty hand. You'll 'know it' when you get it right.
Get a roll of quarters, pass it and pass it. Holding your hands further and further apart, until you can snap it into the opposite palm with hands spread a bit beyond shoulder's width apart.
Then start over with a sharper knife. Do this with bottles and cans at parties, and you will look badass. Do it with a cocktail, and look like a dumbass.
Keep upgrading to sharper and bigger and heavier knives, and for every cut you receive, go back to square one. Don't tell me how clumsy you are. A one-eyed dog could do this with training. And, oh, say, hands! Opposable thumbs? Yeah.
When you can flip a knife into your opposite palm and turn and slash behind you, cleaving a man-sized cardboard target in twain horizontally, and imagine a steaming pile of guts spilling out into his clutching hands, a 'why God?' look on his face, you are ready...
To start all over again with guns. Rifles and shotguns will come later. Advanced course, and a workout. And I suggest you start your gun work with a pistol, a big heavy revolver, and a large automatic. Throwing a .25 is probably the most dangerous, hardest thing to do.
So, hie thee to a toy store, and buy a couple of these new hyper realistic pistols, that cycle and 'fire' when you pull the trigger. Then work with pellet guns. The 8mm soft-pel ones are fine. Load em. And remember that every time you dodge a pellet as it ricochets around the room, that you could have just decorated the place with your brains.
Just remember, start off short, one palm right next to the weapon, and simply place it into your empty palm. Repeat this a billion times or so, and your body will tell you when you are ready to go out to further and further.
Place a move at the end of each pass, once you get used to the transfer move. Make a slash, or a stab, or just turn on the balls of your feet and take a defensive position.
When using a pellet gun, have a waste can (or two) stuffed with newspaper, that you turn and fire deliberately into. You are teaching your musculature and your nervous system to play nice, and get along with each other, and not hurt you.
And to hurt someone else without you even really having to think about it.
This is the place where you step beyond fear, and emotion, and all of those cluttery fluttery thoughts humans allow into their heads, and go Nike, and...
Just do it.
Whups! Forgot the most important part. You need to be able to watch your opponent(s) and surroundings, and to be able to do this in total darkness. so, go get that blindfold on, and get to work.