Page 1 of 2

Coin challenge reopen

Posted: Thu Feb 24, 2011 7:54 pm
by SpudFarm
Hello again, I just got a new camera and decided to test it's video function out on a cannon shot (OFC) just to see how it captures sound and the general image quality.

I shot a small furniture nail at a coin (20 NOR) and I like the results.
I just want to see other small bore guns do the same thing.

[youtube][/youtube]

This video is horrible, I know but it shows what is needed to see. I will do more shots like this tomorrow with better settings if I get the time.

So bring on the destroyed currency!

Posted: Thu Feb 24, 2011 8:43 pm
by ilovefire
what type of metal is is made of and how thick? iv put a .177 steel ball through a 10c Au coin, but then that was from a 27x hybrid :lol:

Posted: Thu Feb 24, 2011 9:11 pm
by saefroch
Challenge accepted. It's a bit dark right now, so I'll try tomorrow after school.

Any limitations on ammo?

Posted: Thu Feb 24, 2011 9:36 pm
by Hotwired
ilovefire wrote:what type of metal is is made of and how thick? iv put a .177 steel ball through a 10c Au coin, but then that was from a 27x hybrid :lol:
You don't need that much pressure.

The last coin challenge was to stick a nail through a coin after we found a clip of some bloke nailing a coin with a ball valve cannon.

Of course much discussion on whether it was real or not ensued so we eventually just did it.

Turns out you don't need all that much to blast a nail in up to the head through a coin especially if it's a relatively soft metal.

Posted: Thu Feb 24, 2011 10:00 pm
by ilovefire
i would have given this ago if it wasnt for the fact that my cane gun is out of commission :cry:

Posted: Thu Feb 24, 2011 10:05 pm
by Hotwired
Well pro-tip for point blank shooting:

Don't use a plastic slug as a pusher for a nail at muzzle touching range.

It flared the tip of my copper barrel when the plastic slug was compressed and elastically swelled inside the barrel on impact.

Posted: Thu Feb 24, 2011 11:18 pm
by jackssmirkingrevenge
Hotwired wrote:Turns out you don't need all that much to blast a nail in up to the head through a coin especially if it's a relatively soft metal.
.. and really you can do it with a needle, it's all about sectional density.

Any details of the launcher SpudFarm?

Posted: Fri Feb 25, 2011 6:43 am
by saefroch
jackssmirkingrevenge wrote:sectional density
Does that even matter at point-blank range? I know I've managed to shoot a drill bit pretty much straight into a target from about 2ft away.

Posted: Fri Feb 25, 2011 6:50 am
by mark.f
Just a thought, but a sabot encased needle out of an airgun might be able to easily penetrate a coin. My rifling is begging forgiveness at the moment, though, so I'll have to come up with a good sabot for the purpose. :roll:

Posted: Fri Feb 25, 2011 7:04 am
by jackssmirkingrevenge
mark.f wrote:I'll have to come up with a good sabot for the purpose. :roll:
Masking tape wrap ;) or a balsa wood dowel.
saefroch about sectional density wrote:Does that even matter at point-blank range?
Of course - think about why high sectional density makes for longer range projectiles:

1) Lower frontal area means there's less of a "cylinder" of air the projectile needs to "punch out" in order to pass through the atmosphere.

2) Higher density means there's more mass behind that frontal area to push through the air, meaning momentum is lost at a lower rate

A projectile with high sectional density travels more for a given velocity because it's better at "penetrating" the air. The same attributes will make it better at penetrating any other medium (although of course projectile hardness will come into play).

Posted: Fri Feb 25, 2011 10:08 am
by Labtecpower
Should I try shooting a coin with my 2" cannon :roll:

Maybe i'll try with my copper gun.

Posted: Fri Feb 25, 2011 10:45 am
by Technician1002
After experimenting with AA battery destruction and sabots, that should not be difficult. Aim with a larger cannon could be a problem. A coin is a pretty small target. This Sabot works fine for AA batteries in a 2.5 inch barrel.

http://www.spudfiles.com/forums/flat-aa ... 21827.html
Image
Image

Posted: Fri Feb 25, 2011 11:00 am
by Labtecpower
Aiming is the biggest problem I think.

And... that must be the most unhealthy pancake in the world :D

Posted: Fri Feb 25, 2011 1:12 pm
by Gaderelguitarist
The same attributes will make it better at penetrating any other medium (although of course projectile hardness will come into play).
I'm sorry, but did anyone else catch this?
Aiming is the biggest problem I think.
What if you construct some sort of apparatus to hold a coin about an inch in front of your muzzle? That or just keep shooting until you hit it.

Posted: Fri Feb 25, 2011 1:16 pm
by Technician1002
I was thinking more along the lines of filling a sabot like the one in the photo above with a couple dozen projectiles all spaced about 1/4 inch apart.. I should be able to get at least 3 or 4 projectiles in the coin.

As far as projectile hardness, the AA battery is considerably softer than 1/2 inch iron plate. :D Iron nails and copper, zinc, silver, gold, or aluminum coins should be no problem. Nickel may be more of a challenge as it is harder.