Both sides of the barrel of a firearm are perforated with a line of holes.
Miniature retractable pistons fill these hollows for seamless tubularity when engaged so rifling and long range accuracy would be sacrificed but...

...ammunition for this weapon would be spherical which would lose some range, but the number of retracted pistons on either side of the barrel would let expanding gas to escape only on that side of the weapon imparting spin to the spherical ammunition.

The more gas allowed to escape on one side, the greater the curved trajectory of the bullet when it leaves the barrel and the gun would shoot around corners at relatively short range depending on charge.
-- 2 fries shy of a happy meal, Dec 31 2015

Guided bullet http://io9.gizmodo....om-over-a-mile-away
[Cuit_au_Four, Dec 31 2015]

Krummlauf https://en.wikipedia.org/wiki/Krummlauf
Very wierd recoil ... [8th of 7, Dec 31 2015]

Magnus effect https://en.m.wikipe...external_ballistics
[xaviergisz, Dec 31 2015]

nerf rival http://www.hasbro.c...bctid=4498969839001
[xaviergisz, Dec 31 2015]

Maybe bolas your bullets ? https://en.wikipedia.org/wiki/Bolas
The three balled laso that seems to go back before time. [popbottle, Jan 01 2016]

Once a bullet (or anything else) leaves the scene where forces are applied to it, its motion becomes straight. For a bullet to curve in flight, it needs to have some force applied to it while in flight. The type of force doesn't matter (aerodynamic, thrust-action/reaction, electromagnetic, gravitational), but if it experiences none during flight, then it will travel straight. Period.

Down here on Earth, since gravitational force is always present, all bullets already do follow curved trajectories. Not what you want, but it had to be mentioned.
-- Vernon, Dec 31 2015


Well dang [Cuit au Four]... ye be bringin a cannon to a musket duel now. How fast can the discharge be curving is all I be askin?

yar
-- 2 fries shy of a happy meal, Dec 31 2015


Sorry [Vernon] we were typing at the same time.

A spinning object affects its own trajectory after leaving its launcher until its spin dissipates. If this were not true then rifling would not have any effect on accuracy. So... helical spin helps straight-line accuracy while lateral spin effects horizontal curvature while longitudinal spin effects (affects?) up-and-down curvature.

Just like a baseball 'after' it leaves the pitchers' arm.

Am I wrong in thinking this?
-- 2 fries shy of a happy meal, Dec 31 2015


They do this with paintball markers (guns). Tippmann Flatline does it by shooting the paintball at an upward angle, but using a curved barrel to correct the flight path back to level. The paintball rolls along the top of the barrel along this curve, gaining back spin. The Warsensor Hop Up has grooves that let gas escape along the top, which is maybe closer to your idea. Backspin increases range, or by holding the marker sideways can result in a curved shot. The general consensus is that they aren't that useful becuase they significantly reduces accuracy, even compared to standard marker that fire spherical paintballs with no spin
-- scad mientist, Dec 31 2015


<link>
-- 8th of 7, Dec 31 2015


/Once a bullet (or anything else) leaves the scene where forces are applied to it, its motion becomes straight/

Go to the driving range and hit a bucket of balls, Vernon. You will be amazed at the trajectories possible.
-- bungston, Jan 01 2016


// hit a bucket of balls //

Is that a euphemism ?

On second thoughts, don't answer that ...
-- 8th of 7, Jan 01 2016



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