deflecting it wouldnt work, swords in general and katanas especially are really weak from side to side impacts. if the shot is centered enough on the target there would theoretically be less movement to draw a katana than to dodge and more importantly less time to do the movement. a thick enough sword would cause the two halves to split at a large enough angle to not hit the person using the sword.
while yes, the trope is kinda dumb, its dumb because the sword would break if its non-magical. the shot most people are taught to take (center mass) is the one most likely to make drawing a sword take less time than dodging the bullet, so no, trying to deflecting or dodging the bullet are not inherently better options
So in real life- obviously no. MAYBE- 1 in a billion. Depends on factors. Katana also actually have VERY brittle blades. The steel is worked so the “spine” is low carbon to absorb force, the blade is high carbon to keep a razor sharp edge. In most of these anime we can assume from the sword play and such we see that these aren’t made like real swords- or the physics doesn’t follow our own- intentionally or by creative license. But the ballistics matter too for our theoretical discussion. Caliber, grain, etc.
A 223/556 like M193 is supersonic or above at the ranges we will commonly see in such a scene. At those speeds any shock or friction may well cause the round to shatter like glass into shrapnel. A high carbon blade would likewise possibly shatter. Now- M198 or a similar steel core penetrator- IF you cut it in half (which then why can’t your sword cut other swords in half...?) you’ve now got two sabots basically. That said- even as a whole round- a single round small caliber penetrator can fail to kill a person for hours or days- rounds with high penetration tend to go straight through flesh- leaving a clean wound and not causing the tissue damage or the shock waves in the wound cavity that rounds which don’t penetrate as well tend to. So
If it’s possible to cut the bullet in half- and you get hit by two small caliber high penetration rounds in non vital areas- you could theoretically survive or even still be in the fight for awhile. Especially in shows like this that tend to have people suffer insane wounds and physical punishment with little or no consequence.
What none of this accounts for- is that our bullet is almost definitely spinning. Outside “zip guns”, antique curios, many shot guns, and futuristic stuff like rail guns- you aren’t likely shooting from a barrel that isn’t rifled. The bummer spins- and even though the cut would have to be near instant- the sword would travel a straight path- relatively- through the bullet- the bullet spins, unequal force is implanted, the trajectory is altered and- depending on the twist rate, the size/length/composition etc of the round the results may slightly differ- but- the bullet would almost certainly shatter and fly off on a trajectory based on the spin, initial trajectory, which parts of the bullet had their velocity impacted and by how much- and so on.
Probably- for the sake of SOME suspension of disbelief- it would at least be better to have the bullet cut vertically- there is some semblance of logic using “cartoon physics” that if done correctly- the fragments or halves could diverge in a way to miss “minute of man” and fly off to the sides of the intended target.
Of course- one final note on the katana- katana bladed are not traditionally or commonly full tang. The blade has a short “nub” if metal at the base, this goes into the “grip” and is secured by a pin which keeps the two pieces (ignoring tsuba etc) together. That pin is known to break. Traditionally it was wood. But even a metal one would be a “weak point.”
Ignoring that a cartoon katana can be magical space metal and not actually have anything beyond its looks in common with a real one- in real life- a skilled swordman/woman- can cause the blade to fall out of their sword simply by how quickly they can change the direction of motion. Several forms are known for this risk- especially where there is a fast “twisting” of the sword- as the design is inherently weak to torsional forces.
So in real life- without some specially made katana designed just to stop a bullet- and even then... the odds of this working are obviously almost none. In a cartoon- it’s still a big stretch and a little effort could at least help it be swallowed at beyond a glance and saying “cool!” I guess in general fiction tends not to be very realistic with weapons- outside certain niches. Gotta love when a bad guy gets shot with a man portable hip fire weapon and flies through the air. “Cartoon physics” vs reality. If a bullet had enough force to make you fly backwards- it would need enough opposite force that the shooter would be thrown as well. Not quite as dramatic a visual spectical.
I guess I’ll drop one more katana fact/weapon fact. So much blood and poop. Like they don’t really talk about or show in fiction the part of pregnancy with the pooping- they usually skip the poop parts with weapons too.
When you disembowel someone- like with a long blade like a sword- and katana in particular involve a lot of disemboweling- the intestines are pressurized. You will very likely get sprayed with poop. Blood too- an open major blood vessel sprays. Even a large vein will shoot blood like a weak water pistol.
Guns aren’t immune either. When Rambo or whoever opens full auto fire from a few feet away and let’s out that primal yell? Yeah. It turns out that many bullets hitting soft tissue acts like a little meat hammer- human Hamburger is thrown about. If you’re screaming- you may get an early lunch. Someone I cared about very much died that way. Went to do his part, for surprised while clearing a building- screamed and shot. Little piece went in his mouth- he got hep and 30 years after he came home- the guy he killed had killed him in that hut and he didn’t even know it.
So I mean- violence is a grizzly business. I almost prefer the “fantastic” version- I think more realistic and procedural stuff is good and enjoy a lot of that- but I think the “let’s make this look cool” way has its merits too. I think the sticking point is that they need to stay internally consistent to whatever rules they’ve created and not break that trust by just doing whatever they think would look cool without any thought to at least the physics within their own world.
Well the sword cutting from where that gif is from I'd say is consistent considering the character in it has cut a shooting star in half whilst star gazing. :) It is absurb, but pretty fun and goofy! :D Though def agree with your points fellas.
while yes, the trope is kinda dumb, its dumb because the sword would break if its non-magical. the shot most people are taught to take (center mass) is the one most likely to make drawing a sword take less time than dodging the bullet, so no, trying to deflecting or dodging the bullet are not inherently better options
But I can agree, more than realism or artist's style, the shit ought to be consistent