Author Topic: New guy question  (Read 912 times)

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Offline arizona44

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New guy question
« on: July 14, 2006, 03:53:08 PM »
Hello everyone, new guy here. Can I shoot sand filled tennis balls from a beercan mortar?

Offline GGaskill

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Re: New guy question
« Reply #1 on: July 14, 2006, 04:55:05 PM »
There are four types of official tennis balls; the diameter range of three is 2.575" - 2.700", the dimension range for the other one is 2.750" to 2.875" (type 3, the slow ball).

The measuring rule follows:

"In all tests for diameter, a ring gauge shall be used consisting of a metal plate,
preferably non-corrosive, of a uniform thickness of one-eighth of an inch
(0.318 cm). In the case of Ball Type 1 (fast speed) and Ball Type 2 (medium
speed) balls there shall be two circular openings in the plate measuring 2.575
inches (6.541 cm) and 2.700 inches (6.858 cm) in diameter respectively. In the
case of Ball Type 3 (slow speed) balls there shall be two circular openings in
the plate measuring 2.750 inches (6.985 cm) and 2.875 inches (7.303 cm) in
diameter respectively. The inner surface of the gauge shall have a convex
profile with a radius of one-sixteenth of an inch (0.159 cm). The ball shall not
drop through the smaller opening by its own weight in any orientation and shall
drop through the larger opening by its own weight in all orientations."


So it would depend on which type ball you use and the bore diameter of your mortar.
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 Double D

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Re: New guy question
« Reply #2 on: July 14, 2006, 07:09:23 PM »
Hello everyone, new guy here. Can I shoot sand filled tennis balls from a beercan mortar?

Yep, if the will fit.  But it's my experience that sand filled tennis balls will come apart.

Why don't you get one of or sponsors to build a mould and and cast up some beer can diameter zinc balls?  I  had Powder Keg open up my beercan mortar to 6PDR and he built me this mould for making zinc  6PDR balls.



Offline Cat Whisperer

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Re: New guy question
« Reply #3 on: July 15, 2006, 03:47:25 AM »
Hello everyone, new guy here. Can I shoot sand filled tennis balls from a beercan mortar?

Yes, but, can you shoot sand filled tennis balls from a beercan mortar safely? 

Probably.

Pressure from behind the tennis ball forces into it forcing the sand forward and out - pressing against the sides.
The question is whether the length of the stack of sand is long enough to allow it to 'bridge' and wedge into place.
You could observe, increasing from light to heavier powder charges, the amount of area on the sides of the tennis ball pressed onto the sides of the bore - to give you an indication of how much it's pressing outward.

When is too much?  Who knows.  With soda-cans filled with water the effect is easy to observe.  At some point the can will actually split along the side.

Tim K                 www.GBOCANNONS.COM
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Chief of Smoke, Pulaski Coehorn Works & Winery
U.S.Army Retired
N 37.05224  W 80.78133 (front door +/- 15 feet)

Offline Dictator

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Re: New guy question
« Reply #4 on: July 15, 2006, 10:36:02 AM »
I cut the tops off the tennis balls and fill them w/ mortar mix concrete They really fly then.

Offline Blaster

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Re: New guy question
« Reply #5 on: July 15, 2006, 02:42:43 PM »
I cut the tops off the tennis balls and fill them w/ mortar mix concrete They really fly then.

OK Joe, just how much of the top portion do you cut off - like 1/4 of it or less???
Graduate of West Point (West Point, Iowa that is)

Offline Dictator

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Re: New guy question
« Reply #6 on: July 16, 2006, 03:44:53 AM »
Hi Blaster Bob, I missed you in Casper this year---take a look below, I cut them right at the seem line. I put hooks in these to attach a steamer to. Then you can see them a lot further out.


Offline threepdr

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Re: New guy question
« Reply #7 on: July 17, 2006, 07:43:47 AM »
I've shot sand filled raquet balls out of my 2.25 inch grenade mortar.  Seemed to work OK, but it did not have a heavy charge behind it. 
See my history and archaeology blog at:  http://erasgone.blogspot.com/

Offline Blaster

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Re: New guy question
« Reply #8 on: July 18, 2006, 06:55:17 AM »
Hi Blaster Bob, I missed you in Casper this year---

Hey Joe.....yeah, we had one of our daughters, her hubby and three kids here over the shootin weekend.  Besides, it was too blasted HOT and expensive to make the drive up to Casper.  Hopefully, next year I'll be there and perhaps have a table to display some of the stuff that I'll most likely be liquidating.  Blaster (Bob in So. CO) -  and it's still hot down here too although the humidity dwells somewhere around a whopping 15 to 20% ;D
Graduate of West Point (West Point, Iowa that is)