First off, humans aren't fast enough to catch a ♥♥♥♥ paintball. And second, you're also ignoring the fact that a bullet is pointy. And pointy things are hard for a blade to cut if they hit it point-first. And besides, all this is useless, even IF you cut the bullet in half, you'll still get killed by the resulting fragments.

No the pieces will just go pass your head I saw it in a tv show

It. Is. Impossible. The brain can't process the information quickly enough, nor can the muscles respond that fast. This ain't FEAR/Max Pa(y)ne (subtle ref).

Notice Kalle's lack of punctuation and obviously incredible information. I believe this would be an example of sarcasm, Metal.
If not: Kalle, you just keep on trucking man.

hollow point lead bullets with like four grains of powder in them vs a katana anchored to a surface and cast out of modern, high-strength steel

or

7.62 mm full-metal-jacket rounds vs a katana swung by an overweight weeaboo with a penchant for collecting dumb wwii merchandise

armor piercing full metal jacket rounds can go through inches of steel, especially in higher calibers
your sword is not even inches wide

Ooh! Ooh! Teacher! I know the answer! The BULLET wins!

Yes, the bullet wins.
Also, Katana do snag on bones, thats why you're trained to cut the areas that have very few of them (the throat and gut), and to stab between the ribs if you're going to suki at all. Regardless, he'd cut himself with it, unless he's actually been trained to use it.

Reaction time aside, as Grif brought out, most katana blades would not even be strong enough to block a bullet. That one YouTube video posted shows a strengthened katana held in place and fired at with a small caliber low power handgun. Regardless, even if you somehow were holding your katana so that a bullet fired at it would hit the edge of the blade in an ideal manner, the resultant fragments could still injure you; hell, the sheer kickback from just blocking something with as much force as a bullet (Newton's 3rd law horhorhor) might either directly injure your hand/wrist or could just stun you long enough for a second bullet to hit you.

You are not ♥♥♥♥ Gray Fox.

For ♥♥♥♥'s sake, it's more feasible to try and shoot a bullet with another bullet. Assuming you have a lot of bullets at your disposable (ala a Phalanx CIWS)

By freak accidents mainly, not really any skill, you could probably cut a bullet with a katana, so it splits into two metal shards.
I like the technique, as long as your goal is to GET HIT TWICE BY THE SAME BULLET.
TWO STONES WITH ONE BIRD, I ALWAYS SAY.

But mostly I'd say if it's any sort of high caliber bullet, or if fired quickly, like with modern rifles, then you're boned. On mythbusters they were able to split a pistol bullet, when perfectly lined up, and then one of those old solid steel ball bullets on an axe (fired at low speeds by an ancient make of rifle).
Then again, with shotgun shells theres no way you're going to block all of them, and a lot of people are probably going to have shotguns.

Lesson learned; if you're bringing a katana, don't piss off the locals.

Hmm. I guess you guys are right. Trying to cut a bullet in half with a katana would be highly impractical and difficult, due to the small size and sharpness of the projectile. If it was bigger and more blunt, though... I oughta try that with an RPG sometime. Maybe it'll work. [/sarcasm]


...I actually knew I was gonna lose this argument. After all, you've got Grif on your side. But I just can't help trying again and again.

The one player Russian Roulette wasn't even neccessary this time. You were arguing that a person could cut a bullet, in flight, with a katana. YOU LOST BEFORE YOU EVEN STARTED.

I'm agreeing with Kultra. A robot couldn't do that ♥♥♥♥.

Actually, a robot might be able to at some point, just not currently. There isnt a large market for robots that cut bullets in half with swords as they fly.

I disagree. Robots are pretty quick accurate etc. I'm sure with proper sensors a robot could block a bullet with a sword.

So you're saying that a robot could, at the current, detect a bullet, determine the angle and speed, figure out at what angle the katana needs to be held at, and use motors in about a tenth of a second? I think it could do the processing bits, but not the physical stuff.