how to make a LOUDER DEEPER boom??? advice please.

[stims]

Hello.  I am new to the board.  I have spent some time looking at old posts and havent found what I am looking for.  I have been messing around with cannons for a while and just finished building a golf ball coehorn mortar.  I have been using FFg about 200 - 250 grains, and packing it really tight with newspaper and or rags.  I just cant get it to sound much louder than a 12 gauge shotgun.  It shoots golfballs great, but I just cant get a deep boom.  the barrel is bored out to about 4 inches deep and an additional 2 inches for a powder chamber.  If anyone has any advice, please let me know.  Thanks.

[GGaskill]

Try to post a drawing of your barrel with dimensions.  I am concerned with the description you have given.

A Coehorn style mortar launching golf balls is not going to give a strong report, even with a heavy powder charge.  There needs to be some pressure when the expanding charge reaches the muzzle and a golf ball does not give enough resistance to allow the pressure to build up.

[Double D]

Hello.  I am new to the board.  I have spent some time looking at old posts and havent found what I am looking for.  I have been messing around with cannons for a while and just finished building a golf ball coehorn mortar.  I have been using FFg about 200 - 250 grains, and packing it really tight with newspaper and or rags.  I just cant get it to sound much louder than a 12 gauge shotgun.  It shoots golfballs great, but I just cant get a deep boom.  the barrel is bored out to about 4 inches deep and an additional 2 inches for a powder chamber.  If anyone has any advice, please let me know.  Thanks.

It's time to stop "messing around" and get serious.  What you describe is more akin to a bomb than a mortar.  If you want a noise maker get a carbide cannon or a blank firing yacht cannon.

What is the diameter of your powder chamber?  For a golf ball Mortar it needs to be about a 1/4 of the depth you mention,  1/2 inch is plenty.  And use a tenth of that much powder--25 grs Fg.  I can only imagine the pressure you are getting with  250 grs of FFg.

If you are getting the boom of a 12 guage shotgun from a golf ball mortar you are getting a lot of noise.  Remember your perspective to the noise.  You are behind it and the sound is being pushed away from you.  Go stand in front of it and listen.

I strongly suggest you visit the safe loads and cannon plans post at the top of our board--read and heed for your safety and the safety of those around you.   

We do not want any new posts in the Cannon accident post.

[Cat Whisperer]

...
I have been using FFg about 200 - 250 grains, and packing it really tight with newspaper and or rags. 
....

You're trying to raise the pressure.  OK.  That works up to a point.  It also has the tendency to blow up the cannon - I know from having seen one explode from 15 feet away shooting blank charges.

Big bangs don't come from shooting golf balls.  They're too light.

Switch to something DESIGNED and BUILT to handle heavy bullets.

(And WELCOME to the board!)

[Artilleryman]

The boom comes from bore size and length of barrel.  In mortars you really don't get a good boom until you get to an 8 inch seige mortar.  Smaller mortars have more of a "crack" or "bang" to them.  This is hard to explain as you have to listen to the different types to hear the difference.

In cannon the small bores have a loud sharp sound.   You really don't get into the deep boom factor until you get to the 12 pdr.

I have read with interest of people on this board that are trying to get a big gun noise out of a model gun.  No matter what you do that isn't going to happen.   What is alarming is that some people are packing what amounts to barrel obstructions in order to increase the sound.  If you want the big sound be prepared to spend a lot of money to get a big gun or join a crew that already has a big gun.

Stims I am glad you joined board.

[stims]

Thanks guys for the advice.  I will lessen up on the powder charges, as it appears I am overloading a bit.  I suppose what it is, is what it is as far as noise is concerned.  If anyone else has anything else to offer, please let me know.  Thanks again.  I will try to post a pict of the cannon, as I think you will like it.