Author Topic: Local Cannon News  (Read 1936 times)

0 Members and 1 Guest are viewing this topic.

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Local Cannon News
« Reply #30 on: September 09, 2009, 10:08:44 AM »
Maybe we should resort to whiffle balls--low mass, high air resistance, short range.  And not very satisfying. 

Frangible bullets used to be used in shooting galleries.  They were sintered iron; iron particles compressed into a solid mass.  They broke into powder upon hitting the target or backstop.  But target and backstop were predictable.  Shooting the same bullet in the field would give unpredictable results since it is not hitting a massive target at nearly 90 degrees.  A bursting shot would be better but uncle and his socialist friends are afraid of ordinary folks using such things.  Kind of like silencers--general ownership would cause a tidal wave of murder.  Riiiiight.
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline Cannoneer

  • GBO Supporter
  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 3950
Re: Local Cannon News
« Reply #31 on: September 09, 2009, 11:32:50 AM »
Maybe we should resort to whiffle balls--low mass, high air resistance, short range.  And not very satisfying. 

The NERF (Non-Expanding Recreational Foam) ball would probably make for a more accurate projectile, seeing as its more solid form would be more apt to overcome the effects of wind deflection. :D

 
RIP John. While on vacation July 4th 2013 in northern Wisconsin, he was ATVing with family and pulled ahead of everyone and took off at break-neck speed without a helmet. He lost control.....hit a tree....and the tree won.  He died instantly.

The one thing that you can almost always rely on research leading to, is more research.

Offline subdjoe

  • Trade Count: (0)
  • Senior Member
  • *****
  • Posts: 3036
  • Gender: Male
Re: Local Cannon News
« Reply #32 on: September 09, 2009, 12:21:38 PM »

 Using a plastic cup (closed end on top of the charge) filled with bird shot/beeswax should stay together in flight but lose a lot of mass as soon as it deformed/split upon impact.

Watch this: [yt=425,350]<object width="560" height="340"><param name="movie" value="http://www.youtube.com/v/dtZkBAEbRBk&hl=en&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/dtZkBAEbRBk&hl=en&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="560" height="340"></embed></object>[/yt]

At about the 2:40 mark you see what is mislabled as grape shot, really home made cannister.  A #1 Tall can, filled with .69 diameter lead roundball, the can then filled with wax.  That is out of a full scale, smooth bore 3" Griffen Gun, 8 oz. of cannon grade powder.  We were finding the cans, or parts of them, about 30 to 50 yards from the muzzle.   
Your ob't & etc,
Joseph Lovell

Justice Robert H. Jackson - It is not the function of the government to keep the citizen from falling into error; it is the function of the citizen to keep the government from falling into error.

Offline Victor3

  • GBO Supporter
  • Trade Count: (22)
  • Senior Member
  • *****
  • Posts: 4241
Re: Local Cannon News
« Reply #33 on: September 10, 2009, 01:48:46 AM »
 Cool video 8) I like 2:08....

 I see what you're saying with a large metal can and 1/2# of powder, but something like a #9 shot-filled pill bottle on top of 300 grains might be different.

 As an alternative, forget the wax and use some kind of sealed plastic container that would get to the target intact. I'm thinking something like this could be designed to break open as soon as it hit the dirt, spilling the shot (?)

 No projectile is going to be completely safe (if it was, it wouldn't be good for much). However, it would be nice to come up with one that could do the job on a 100 yd target but not retain much energy at 500.
"It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

Sherlock Holmes

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Local Cannon News
« Reply #34 on: September 10, 2009, 04:09:34 AM »
However, it would be nice to come up with one that could do the job on a 100 yd target but not retain much energy at 500.

Conceptually, this is pretty easy.  Make it low mass and low ballistic coefficient and use a low powder charge.  That way it will not have a lot of kinetic energy to begin with and it will lose what it has quickly.  But the trajectory will have a lot of curvature.

How this works out in practice would depend a lot on bore size and rifling or not.  I'll bet with low powder charges, you could make projectiles from wood that would be adequate for 100 yards.  Time for some experimenting, but not out the front door.
GG
“If you're not a liberal at 20, you have no heart; if you're not a conservative at 40, you have no brain.”
--Winston Churchill

Offline Victor3

  • GBO Supporter
  • Trade Count: (22)
  • Senior Member
  • *****
  • Posts: 4241
Re: Local Cannon News
« Reply #35 on: September 11, 2009, 01:17:44 AM »
 Maybe a turned plastic one? Teflon is pretty hefty, and squishy enough to deform into rifling. Plastic would probably work best in a breech-loader with a driving band rather than an expanding base in a muzzle-loader (my 30mm barrel was designed to use a projectile with a plastic driving band).

 You're right about bore size & rifling; something from light material less than 1" might be useless. An un-rifled larger bore probably wouldn't be very accurate with light material other than in a ball.

 I still think that a heavy, shot-filled capsule of some sort would be better out of a smooth bore. Something like one of these items...

http://www.skylighter.com/fireworks-making/shell-parts.asp

 Or maybe....

http://www.buckaball.com/proddetail.asp?prod=GF065P
"It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

Sherlock Holmes