Author Topic: Best choice for a powder chamber in a golf ball mortar.  (Read 620 times)

0 Members and 1 Guest are viewing this topic.

Offline Doc Brown.

  • Trade Count: (0)
  • Contributor
  • ***
  • Posts: 442
Best choice for a powder chamber in a golf ball mortar.
« on: September 15, 2012, 01:10:57 PM »
Anyone know what size a powder chamber should be in a golf ball mortar. I want it to be loud as possible.
 
Im using a 4" by 8" bar of 304 stainless and im going to bore it out to 1.695 and im trying to figure out the best size for the powder chamber. Also does this mortar im attaching a picture of seem like its tapered the whole length of the barrel? Thank you.
 

Offline The Jeff

  • Trade Count: (0)
  • Contributor
  • ***
  • Posts: 255
Re: Best choice for a powder chamber in a golf ball mortar.
« Reply #1 on: September 15, 2012, 01:40:32 PM »
On my 1840 seacoast mortar I drilled a 5/8" powder chamber deep enough to hold 100 grains. I'm partial to long narrow powder chambers because (at least from what I've read) people have had ignition issues with a wide powder chamber and light loads.


45 grains FFg will get a steel Fox ball to 100 yards, and I've estimated 100 grains will send it out to 400-500 yards. It doesn't take much to launch a plain golf ball out of sight.

Offline Double D

  • Trade Count: (3)
  • Senior Member
  • *****
  • Posts: 12609
  • SAMCC cannon by Brooks-USA
    • South African Miniature Cannon Club
Re: Best choice for a powder chamber in a golf ball mortar.
« Reply #2 on: September 15, 2012, 02:08:42 PM »
Anyone know what size a powder chamber should be in a golf ball mortar. I want it to be loud as possible.
 
Im using a 4" by 8" bar of 304 stainless and im going to bore it out to 1.695 and im trying to figure out the best size for the powder chamber. Also does this mortar im attaching a picture of seem like its tapered the whole length of the barrel? Thank you.
 


Do you want loud or do you want a mortar.  The two are not necessarily compatible.

If you want to determine correct chamber size first determine maximum diameter of chamber your  barrel stock will allow.   Barrel diameter over chamber divided by 3., that is your chamber diameter.   Look that diameter up in the same loads sticky at the top of the board.  Bore a hole in a piece of wood the diameter you determined for you chamber until it is deep enough to hold the  maximum powder charge shown in the safe loads sticky.

If you ar just makeing a noise maker that 1.695 bore diameter will be fine. If you intend to shoot golf balls then your bore needs to be 1.72 inches in diameter.

Offline GGaskill

  • Moderator
  • Trade Count: (2)
  • Senior Member
  • *****
  • Posts: 5668
  • Gender: Male
Re: Best choice for a powder chamber in a golf ball mortar.
« Reply #3 on: September 15, 2012, 02:16:10 PM »
If you really want noise from a  model mortar, you should bore it like a cannon with a small bore the length of the piece.  The large bore section causes a major drop in muzzle pressure (which is the primary source of noise), especially if you are firing blank loads.  Shooting golf balls will not give you much noise because the ball has so little mass.
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