Showing my ignorance

[brokenpole]

Okay ya'll it's time for me to show my ignorance.

I have read a couple of threads here that talk about using billard balls as a projectile for a mortar.  In most cases the conversation turns to windage past the projectile.  Then there are people that talk about wrapping tap around the projectile to cut back on windage.

Is there a set amount of windage that you should try to maintain?  When I got my juice can mortar it was bored with a 6.5 oz juice can in mind.  In fact I even sent a sample to the maker to be sure.  For the most part that is my projectile of choice.  So I never gave the idea of windage much thought.

This idea of shooting billard balls sounds so enticing but I don't want to mess up my mortar.  I don't have a set of measuring tools so I cannot get an accurate size on the muzzle.  But if a pool ball drops easily down the muzzle would it be okay to shot.

As for powder load I wouild follow my normal trial and error method.  Start low and work up slowly (staying well away from the thing when it goes off) til I either get the range I want (~100 yards).

So any thoughts/help would be greatly appreciated.

[irishman]

Brokenpole,

     You have been a delight to communicate with! The rule of thumb is to divide the diameter of the projectile by 39, then multiply by 40 to determine the appropriate bore diameter.

                                                   Michael

[brokenpole]

Thanks Irishman...

Now I have to take my shoes off.  I will need my toes to do that cipherin   

[Double D]

brokenpole,  You might want to visit our stickies posted at the top of the board.  You most likely will find the answers to most of your questions there and just by accident while there you will see a bunch more neat stuff also. 

Just the same you can still ask your question here and you'll get help.  In the sticky post called safe loads and cannons plans you will find a link to your question about loads, including a chart to help find the load for you size bore.  For mortar's the bore diameter for determining safe loads is the diameter of your powder chamber.

[brokenpole]

DD I have went through the stickies and I write down ideas and questions.  But I never seem to write down what post they are in.  I was just looking at the site and realized that there is a bookmark feature.  What a great idea?

Thank you for putting up with me.  I will get the hang of this stuff.  I have figured how to post pics.  Here real soon we are going to tackle video!!

I would like to say thank you again to Mike...aka irishman for directing me here.  My wife has her message board that deals with spiders and I have this one.

[subdjoe]

Hey!  You were smart enough to ask here.  That isn't ignorant at all.  Purtty durned smart iffen ya axe me.

[GGaskill]

I don't have a set of measuring tools so I cannot get an accurate size on the muzzle.

You really should get yourself an inexpensive 6" dial caliper.  Here is one on sale.  Here is another one on sale.


But if a pool ball drops easily down the muzzle would it be okay to shoot?

Yes, assuming it goes all the way to the bottom.  The windage is to prevent the shot from getting stuck in the bore.  Since we don't have to repel charging infantry, we have time to clean the bore between shots, so if the shot goes in easily, it will come out easily.  If you work up the load from a light beginning, you will be OK.

[Rickk]

Not all pool balls are the same size. A ball gauge that is slightly under the smallest diameter of your bore is a handy thing to have. Rule of thumb is to make the gauge 3x the diamter, and allow the ball to roll down the gauge.

[GGaskill]

That's three times as long as the diameter so there will be a good chance of covering all the diametral possibilities.