Mortar/Cannon CONTEST - in the planning stages now.

[Cat Whisperer]

I have some DOM tubing  which I think the DOM tubing is 1144 stress proof which is 2" OD and 1.495" ID.  The pieces I have are all about 6" long.

DD has some OAK.

That, plus public recognition for your individual and collective insanity is the reward.

We are in the planning stages now for the 'contest'.  The general idea is that if you send us the postage we'll send you a piece of tubing and a chunk of wood from which y'all will hand-craft (or hire someone to do so) a replica mortar or cannon.

Of course safety and legality are foremost followed quickly by fun and satisfaction.

Categories are being created as we speak.
- best crafted
- loudest
- most accurate (shooting)
- most accurate replica
- design simplicity
- design ingenuity
- etc. etc.

Well -?

[Powder keg]

All right another project. I'm in.  Powder keg

[Double D]

Here's my idea on it.

You must provide a dimensioned sketch, suitable for others to make their own mortar.   Drawn out on the side of an old cardboard box with a crayon would be fine as long as some one could  take it and make their own gun.

The oak will be cut proportional to a standard Coehorn base.   You don't have to make a coehorn, but the do have to use the wood and steel we furnish. You  can use more  wood and more steel of you own.  We should limit it to mortars only.  Mixing cannons and mortars makes the last step a little hard.
 
International competitors welcome, after all you are going to pay the postage for the steel and oak.
 
Lets say you have 6 months to make the gun, post on this board the drawing and pictures of the finished gun and then fire it.  To make it uniform I would say let's stick to golf ball bore and you must shoot golf balls.

The last step is to fire a mortar match just like at the N-SSA matches at Ft. Shenandoah.  Little shorter range.  Post at 30 yards.  10 rounds, total aggregate distance for the best 7 shots.  30 yards is picked as the direct scale down from the 24 PDR bore of 5.68  to the 1.68 bore of the golf ball.
 
Prize...prestige, board bragging rights
 
Your thoughts on that.

[Double D]

We really would like to hear other thoughts on this...

[CU_Cannon]

Sounds like a neat idea.  I would be in.

[CU_Cannon]

Another idea is to have a peopleÂ’s choice category.

[50bmg]

Guys, I'm interested, not going to camp Perry this year.
 Sign me up please!
 50bmg in IN.

[guardsgunner]

I would give it a go.

[Double D]

- most accurate replica
The most accurate replica should probably require a picture or drawing of an original being replicated. As well as detail photos.

- design simplicity
- design ingenuity
- peopleÂ’s choice category
These category winners would be decided by a vote of board members.

I have removed loudest because there is no way for us to guage that.

The shooting contest will decide the most accurate.

A question to the board, would the moderators be allowed to participate?

[guardsgunner]

If all members of the board were judges: then being a moderator (judge ) would have of no advantage.
   But, would it really make a differance anyway. There ain't a million dollars a stake here.
   Ok by me.

[Double D]

By my count there are only 6 people interested in this project.

CW
DD
Guardsgunner
50bmg
CU_Cannon
Powderkeg

Are there any others?  Any lurkers?  Rember you don't have to build this yourself, you can have it built.

We are asking so we can get the logistics set up.  We need get the steel and oak in the same place. CW and I need need a count of how much steel and oak we need to move where.

We will be sending you out one piece of 2" x 6" DOM steel tube with an I.D. of 1.495" and one 10" x 10" x 2" piece of white oak.  These two items will fit in one of the post offices flat rate mailing boxes.  We are only going to charge you the flat rate mailing fee of $7.70 for the material. If you need additonal wood or steel you will have get that yourself.

So who else is in?

[GGaskill]

Assuming a bore of 1.7", the wall thickness is going to be only .15" with no decoration.  Even with low mass golf balls, that seems kind of thin.

Otherwise, I am interested.

[Cat Whisperer]

Now is the time for some serious proof testing.

I have one built - fastest one has come together for me - from two pieces.  One piece is the DOM tubing, bored to 1-1/2 golfball depth at about 1.70 inches in diameter.  The other is a round of 1144SP cut to 1.69 at the top for about 3/8 of an inch and the lower body is cut to about 1.490 (which slides into the origninal diameter of the tube).  So the powder chamber (which in time tested theory) handles the high pressure and as the gasses expand (and lower in pressure) they push the golf ball out the tube.

This is the whole theory behind Coehorn's invention in the 1700's of the powder chamber.

Tune in tonight - I'll post some pix.

[Double D]

That's what this contest is about.  How can you use this piece of steel to make a golf ball mortar?

We are going to give you the steel and wood.  You can add more steel and add more wood.  You use creativity and ingenuity to make the mortar.

I have some ideas on how to do this. Since this is a contest, I'm not going to share them now...after I win, yes!  Not now.

[GGaskill]

Send you the money and you send the materials?  Send the money to where?

[Double D]

We still working on the logistics.  Give us a few days and we'll post the details.

[CU_Cannon]

PayPal would probably be the easiest way of transferring the money.

[GGaskill]

I would rather not go there.

[Cat Whisperer]

Take these as no more than rendering in steel some ideas of golf-ball caliber.  This has not been proof tested nor even fired.

What it does show you is a 5" piece of DOM tubing 2.00 OD and 1.495 ID that has been bored to 1.7 or so for most of it and a piece of 1144SP that has been cut to just under 1.7 at the collar and just under 1.495 for the rest.  It has a 1/2 diameter powder chamber flared out a bit, that will hold about 40 gr of fffg filled to the bottom of the flare.  Also shown is a piece of the 1.75" diameter 1144 stress proof.

[Double D]

As soon as the steel gets here from CW I will post the rules and instructions.

I am a little nervous about the shipment coming from CW. He sent me this message via email about the box:

I can get about 50 lbs of IR'N in it.
I'll take a couple of days to build up the fiberglass reinforced tape to dry - a layer at a time

I may have to blast to get the box open.

I have sent payment via Paypal but have never recieved money that way.  I'll have to look into it.  Generally I go cash or U.S. Postal money order only.  The fee is going to be $7.70.  That's the new U.S. Post Office flat rate fee.

As soon as CW sends the shipment up..and I can get the box open I will post an announcement with instructions.

[Cat Whisperer]

56 lbs 6.6 oz.  headed your way.  Should be lots of extra to play with.
Insured.  It is dangerous only if you drop it on your foot or pick it up the wrong way and  pull a muscle or slip a disk.

They said 3 or 4 days.

[Double D]

CW,

You must have got the evil eye when you presented the box to the clerk!

I see the cast bullet guys hav grabbed onto this method  of shipping.

[GGaskill]

CW mentioned 1 1/2 inch golf balls back a few posts.  Where does he buy these?

[Cat Whisperer]

CW mentioned 1 1/2 inch golf balls back a few posts.  Where does he buy these?

I did mention boring to a depth of 1-1/2 golf-balls (1-1/2 calibers in depth) - often the length of a tube is measured in the number of diameters of the bore.

The 1-1/2 ID (of the original tube) was bored to 1.70 to fit the 1.68 golf balls.

MOST golf balls will easily slide through 1.70 BUT I have a few (red in color) that won't.

[GGaskill]

OK, now I understand.  My bad.

[Cat Whisperer]

No problm. I too wish that there was a good source of commonly available (free) objects that  were 1.5" in diameter (or would fit with sliding fit into 1.500").

When I get good at cutting radii - especially internal, I'll use the 1.75" OD 1144SP for spherical moulds to fit the DOM.

[Double D]

Tim,

I can only think of three ways you could cut the bottom radius in that mortar.  Tracer, CNC and form reamer.  I can imagine be able to cut the radius witha an outside mouted tool.

One other idea is a shaped tool point on a spade drill.

Of course cutting in the face a breech plug would work also.

[CU_Cannon]

I used a ball end mill for the powder chamber on my golf ball coehorn.  I drilled the hole at 7/8" and then used the end mill to finish it to 1".  I used a slow speed and a lot of cutting oil.  You had to keep pressure on it as it was cutting other wise it would start to chatter.  The chamber turned out good, clean looking and smooth.

[Double D]

I got this box on my front step this afternoon.  It's one of the post offices new flat rate bulk boxes.  3 of the four corners were ripped out, but it didn't look like anything came out.  The box weighed in excess of 50 lbs.  Boy I'll bet the Mail carrier is cussing CW and me!!!

So the contest is on!  I already drew up one sketch of an idea.  An now have another to work out.  

This gonna be fun!!!

Send me a PM if you want in and I wll send you my snail mail address to send the shipping costs.  I am also going to use-try paypal for those that want.

"scuse me I got  go draw....

[Double D]

Anybody else in?

There are couple of you fellows I haven't heard from yet.