Thursday, January 19, 2017

solving a problem with nerf darts.

A common problem with Nerf darts being shot from a modified Nerf Blasters is the inaccuracy and instability of the darts in flight.

Darts tends to "fishtail" in mid-flight. this is partly due to the design of the darts, and the way it fires.

Unlike modern firearms that have rifling within the barrel, which provides a spin to the munition that they fire, thus increasing the stability of the projectile in flight, making it more accurate.

Nerf blasters lack any rifling at all, similar to smoothbore muskets in history. coupled with the poor design of nerf darts, makes it pointless to have a powerful blaster. unless you can improve the stability of the darts in flight.

Quite awhile back, Nerf community members have found that by reducing the dart down to 3.5 cm, it would reduce air drag on the dart and make it fly further with a slight improvement to accuracy.

But darts still aren't hitting their target consistently and fishtailing, although reduced, is still a problem.

so, to reduce the fishtailing effect on the darts, I decided to try my hands at making a barrel attachment that will induce a spin to the darts, enough to improve its stability in flight and thus reducing or eliminating the fishtailing effect.

initial attempt:
muzzle attachment - 0.5mm rifling
blaster - retaliator with artifact punisher kit, 8kg spring
 Results:
Significant increase in accuracy with a slight drop in range.

Possible Reasons:
The rifling helped induced a spin to the darts, hence stabilizing the dart in flight.
OR
the rifling reduced the dart's velocity due to friction and made it less prone to fishtailing


second attempt:
muzzle attachment - 0.75mm rifling
blaster - retaliator with artifact punisher kit, 8kg spring
Results:
Slight increase in accuracy with a severe drop in range.

Possible Reasons:
The rifling was too thick and induced too much spin due to friction from the rifling. this reduced the velocity too much and cause the dart's range to drop severely.
Would need a stronger spring if this was to work better.

Another thing that I tried was to use the darts own tip to induce the spin. I tried designing a dart tip with little notches at the side to induce pressure and spin the dart.
will need excessive testing and most likely would do a CFD test to test our the design (that's for next time)


Prototype dart tip design

No comments:

Post a Comment