HELP....PLEASE....HELP

[motocam25]

I built a BB mortar and it will not push the ball farther than 20 feet. I DO NOT have a powder chamber (yet). I am using a O2 tank. We are putting the powder directly in the bottom of the tank. I think my issue is that there is too much space between the bottom of the ball and the powder OR the powder is spread out to much because it is in the bottom of the tank. It doesn't matter if you wrap the ball for a tighter seal or not. Same result.

I have a powder chamber being made at the machine shop now, but if the distance from the bottom of the ball to the charge is the problem, am I wasting my time??

Any help is greatly appreciated.

[Artilleryman]

What kind of powder, and how much are you using?

[motocam25]

We used Pyrodex, then tried regular black powder. Same result. Thanks

[Rickk]

wait for the powder chamber. If you get enough pressure to seriously move the ball in the full diameter of the O2 cylinder base you may make the newspaper headlines in a bad way.

[Double D]

What is the dimaeter of the cylinder and the bowling ball.

How much powder did you use?

[GGaskill]

Does the ball go all the way down against the curved part of the cylinder?  Also, you say the bottom of the tank.  Does that mean the squarish true bottom of the tank?  You should be using the end with the neck.

[motocam25]

Ball goes all the way down, and as far as powder, we started with a 35mm film canister, then 2, then 3. Same result.

[Double D]

You really should wait for the powder chamber.

Actually you got pretty good results for amount of powder you used. 

Here is a link to a post we have here on one bowling ball mortar

Bowling ball mortar

Which leads to another at: Bowling ball specs

and another...  A Florida Bowling Ball Mortar

and still another 'bout ready to blast a bowling ball

Boy talk about a trip down memory lane...CW you getting all misty eyed, this goes way back!

[Double D]

Can't forget this one...Jim Waits Mortar

I think if I remember right it was shortly after Jim completed this mortar he passed away.

[Cat Whisperer]

Yea - I've been collecting bowling balls for a few years now (at $1 each - no more) in hopes of someday finding the right sized tank.

[motocam25]

I guess my cylinder is a bit oversized, maybe1/8th inch. I wrapped an old towel around the ball and tamped it down, and WOW!!! That thing touched the clouds!!!

[Double D]

I guess my cylinder is a bit oversized, maybe1/8th inch. I wrapped an old towel around the ball and tamped it down, and WOW!!! That thing touched the clouds!!!

Maybe not!

A bowling ball gun with proper windage would need a minimum bore of 8.815 inch.
Circumference of a bowling ball.  Max 27.002 inches.  27.002 xi .31831 = 8.595 maximum diameter of a bowling .  (8.595/39)x40= 8.815 inches http://www.topendsports.com/sport/tenpin/dimensions.htm

What is the dimaeter of your tube and what is the diameter of your ball.  How much powder did you use?

Patching balls over 1 inch is generally not recommended because of the potential sharp pressure increases.  If you were able to slip the ball down the bore easilly enough you probably weren't that tightly patched.

[Cat Whisperer]

Let me echo DD's warning of caution in the strongest possible words - DON"T.

Unless perhaps you've inspected EVERY square inch of the inside of the tube,
Unless perhaps you've taken the trouble to hone it to a MIRROR finish,
Unless you checked the applicability of your personal life insurance AND liability insurance.

No, NO Unlesses.  The possibility of a pressure spike from a wedge condition is there.

If it works, you get bigger bang, more velocity and range. 

IF IT WEDGES, YOU LOOSE.  We'll read about it in the national news.

Kindly reconsider.

Clearance (windage) is there for a reason.  However motivating the excitement is, it is well worth taking the proven, safer route.

[dominick]

I guess my cylinder is a bit oversized, maybe1/8th inch. I wrapped an old towel around the ball and tamped it down, and WOW!!! That thing touched the clouds!!!

   Definitely not good news,  Being in the welding business,  I have seen more than a few oxygen cylinders completely split down the side. And that is from the 2000 psi maximum they are usually pressurized to.  Dom

[Cat Whisperer]

....
Being in the welding business,  I have seen more than a few oxygen cylinders completely split down the side. And that is from the 2000 psi maximum they are usually pressurized to.  Dom

THANK YOU for sharing this.  I'd heard (well documented with pictures too) stories of O2 tanks that fell over and knocked off the valve - landing some good fraction of a mile a way in someone's basement after going through the front yard.

But knowing that a regular form of failure is a side split gives one pause in the the process of designing a bowling ball chucker.

[GGaskill]

Yea - I've been collecting bowling balls for a few years now (at $1 each - no more) in hopes of someday finding the right sized tank.


Here is a shot of most of my bowling ball collection (4 balls to a box, and there are some boxes behind the large stack.)

[Cat Whisperer]

Aaa HAH!  Trying to corner the market!

Anyone for league bowling?   (black powder that is)