Would it funnel air in a way that would make it travell farther?
Would it have superior armour pearcing abilities? (It hits the object and screw’s it’s self in)
All the bullets I’ve seen have been conical, but it couldn’t be that much harder to make a screw shapped bullet, so why don;t we have screw shapped bullets
Rounds fired from most modern firearms is already spinning in flight. Unless it is a shotgun, the barrel of a pistol or rifle is grooved in a spiral pattern, which causes this spinning. Thus , there is no benefit to putting the spiral pattern on the bullet to get it to spin (exception: some slugs fired from shotguns are groved to try to impart spin).
The downside is that the “threads” on the round would increase aerodynamic drag in flight. This would reduce the range of the weapon, increase the rate at which the bullet drops, and probably cause chaotic effects on the flight path. Bottom line, a less accurate round the doesn’t go as far.
…[strikeout]the[/strikeout] that doesn’t go as far.
Preview is my friend, preview is my friend, preview is my friend…
IIRC the rubbing against the rifling does cause shallow angled grooves in the surface of a bullet as it passes through, but they are not sufficent to create spin.
Bullets already leave a barrel spinning at something like 10,000 RPM (your rifling may vary).
IIRC the rubbing against the rifling does cause shallow angled grooves in the surface of a bullet as it passes through, but they are not sufficent to create additional spin.
Actually, an M16 bullet leaves the barrel spinning at something like 5500 revolutions per second - muzzle velocity is about 3200 fps, rifling rate is 1 rev per 7 inches - the math leads to 5485 revolutions per second, or 330,000 RPM. Of course air resistance quickly slows down the bullet’s forward and rotational velocities.
Armor piercing capacity is a function of hardness and velocity - it’s moving too fast for any sort of “screwing it in” effect to occur - imagine throwing a drill at a piece of wood.
Bullets don’t really spin that fast compared to their linear speed either.
Look at it this way: The spin is imparted by the rifling, right? Rate of twist in a rifle firing elongated conical bullets would be something like one turn in twenty inches. In something firing stubbier bullets the proper twist rate is slower. For round-ball, it’s something like one turn in six feet. Let’s take 1:20" as a fast rate.
So now your bullet is flying down range and it goes straight through a man-sized target. How thick is this target, maybe twelve inches?
So while it’s in there, you bullet makes a little over half a turn, assuming the spin didn’t slow down appreciably due to drag.* It’s not exactly screwing itself into aything.
*Fair assumption, I think. Flight times for these things isn’t measured in hours.