new to cannons please help

[busadave]

i just bought a cannon,its made from 4140 steel,it is 5" tall and 3 1/2" wide at base tapers down to 3" wide at the end.the bore is .060 its a golf ball mortar.its 4" deep with a tapered powder pocket.weighs about 13lbs.the guy said he uses 400 grains to shoot a golf ball.well im not shooting golf balls,its just for the 4th of july.to make a big boom.so i asked whats the max load i can use,he told me he uses 1500+ grains when shooting and up to 2000 grains of black powder.now im not saying he doesnt know what hes talkin about but from what ive read on here thats way too much.please help before it gets here so ill know what a safe measurement would be.it has a 1 yr unbreakable guarantee..

[Cat Whisperer]

Start with your normal charge and work up to twice that.

Use a piece of cardboard over the powder.  Some folks soak the cardboard (and dry it) with baking soda as a fire-retardant.

4140 is good steel.  At some point you will be just making more smoke and flame, so you shouldn't have to go any further than perhaps twice normal loading.

[m223]

Busadave, It is a good thing you came here, there is a wealth of information on golf ball mortars, and the proper charge weights. 2000 grains is nuts, 1500 grains is nuts, I know your new, I am too. I want you too have a good time and be safe. I would say use ffg black powder only to start with. Also if you do shoot a golf ball start at around 40 grains and work up, it won't be much fun if you can't see it arc through the air. For blanks use the cardboard disk over 90 grains and work up. Like I said spend some time researching the forum you will find a ton of helpful information. Welcome aboard and have a safe 4th.    Tracy   

[Rickk]

http://www.cannonthunder.com/index.html   your "cannon" maker, correct?

2000 or even 1500 grains is a hell of a lot of powder. I suspect that the short barrel is all that keeps the pressure down below "grenade" level. If that is any where near correct, you are largely wasting powder at that quantity. If it actually is able to burn completely, you are on the edge of a trip to the e-room.

You also did not mention that granulation of powder you are using. You are in that grey area... 2F is probably OK for reasonable loads with blanks, and 1F  balls unless you back charges way down (like under 100 grains). Well under 100 grains is where you want to start experimenting with a golf ball anyway... 40-50 grains sounds about right to me as well.  A couple hundred grains of 2F with a cardboard wad for a blank sounds way more sane than what he recommended.

The baking soda wads are a good thing to prevent fires by the way. I started using them after I lit my wife's garden on fire and others have caught on to the trick as well.

[doubleduece]

Welcome to the forum. I have the mortar you bought. The 1500-2000 grain charge he has used was to test the integrity of the mortar. I don't think he would recommend nor do you need that much powder to make a nice blank boom. He normally uses 250-400 grns of FFg. I have shot 400 grains from it, but you do not need that much. If you are wanting noise maker start with 100 grains with the cardboard and move from there. You will see that there is a point where you are just burning powder but the effect you want does not increase.

[longcaribiner]

making a boom for the sake of noise is a factor of a couple things.  Not just the powder, but the weight and compression of the wads as well.  Black powder burns slowly and just for an example, in a 20 inch 50 cal barrel, loading more than 90 grains justs wastes the extra powder is muzzleflash because the powder isn't fully consumed before the patched ball leaves the muzzle.  A patched ball has both weight and a certain resistance to being pushed down the barrel.  A plain cardboard wad doesn't have the same weight as a lead ball and offers less inertial weight to resist the powder.  This lack of resistance often means the cardboard wad just gets pushed out the muzzle with a whoosh instead of a bang.  In my 75 cal iron cannon, (I was told it was used for starting sail boat races on Lake Erie in the early 20th century)  I found that two heavy card wads and 70 grains of powder make more bang than one wad and 100 grains.  The wads I speak of are 1/4 inch thick paste board wads.  These wads are a rather tight fit and need moderate force to "ram them home"    I tried fibre 10 ga shotgun wads and found they weren't as tight a fit and it required three of them to get a bang. 

A friend of mine makes inch thick wads by soaking shredded newspaper in water with just a touch of white glue and then mashing the mixture into pvc moulds and letting it dry into a thick cake    It is then alot like the consistency of the gray homosote that use to be sold at lumber yards.    He puts a dry corregated cardboard wad over the powder and then the home made news print wad that has been lightly misted with water to make it damp. 

The problem with the wads I and my friend use is that they can be dangerous projectiles as well.  (I accidentally took a hefty branch out of a neighbor's tree one 4th of July with just pasteboard wads.   

All that being said, I just happen to have a new box of Winchester 10 ga blanks here on my desk, (for my little Winchester breechloader cannon)   They make a rather fair kaboom and I see it says 8dr equivalent.  I think"equivalent" is the key word.  8 drams would be around 200 grains of powder.  I seriously doubt that much powder and a wad even fits in these shells.  The tops of the shells are crimped over and must take a fair amount of force to blow the wad up through that crimp.   

[Rickk]

If your 10G shells are loaded with smokeless, there is not 8 drams in them. If they are loaded with BP, there more than likely is 8 drams.

For reference, a 2-3/4 inch 12 gauge shell will hold 6 drams of BP with ease.... been there, done that.

[longcaribiner]

The Winchester box says the 10 ga shells are loaded with black powder.  What granulation and how much, who knows???  I have fired it at night and there isn't a really big muzzle flash.   

I also made an insert to fire blank loaded 45-70 shells out of it and another insert to fire 5.56 Nato blanks that I got a deal on. .

[busadave]

yes rickk thats the maker of my cannon,this is my 1st cannon.my buddy has got me in the hobby now.he has a steel pipe it weighs like 40 lbs.triple welded on the back and its 19 in long,2 in bore and 3 1/3 in diam, he shoots 1500 grain out of his and sounds great.now the cannon im getting, ive emailed the guy like 5 times wanting info on how many grains i can shoot. he sais he plays with 400-500 grains.im not shooting golf balls just blanks for a boom.ive looked at every page on here and read alot of post and most of them say 400-500 grains.but the guy still said i could do 1500 if i wanted to.and thats what he does and more.i just dont want to get hurt or anyone else.so ill take everyones advice here and start low and work from there.

[Double D]

yes rickk thats the maker of my cannon,this is my 1st cannon.my buddy has got me in the hobby now.he has a steel pipe it weighs like 40 lbs.triple welded on the back and its 19 in long, 2 in bore and 3 1/3 in diam, he shoots 1500 grain out of his and sounds great.now the cannon im getting, ive emailed the guy like 5 times wanting info on how many grains i can shoot. he sais he plays with 400-500 grains.im not shooting golf balls just blanks for a boom.ive looked at every page on here and read alot of post and most of them say 400-500 grains.but the guy still said i could do 1500 if i wanted to.and thats what he does and more.i just dont want to get hurt or anyone else.so ill take everyones advice here and start low and work from there.

Pipe is a seamed thin wall material intend for low pressure application not suited for cannons

Safety rules call for the wall thickness to be  1 caliber thick.  So if the bore is  2 inches then the walls should be  2 inches thick and the dimaeter of the tube should be 6 inches in diameter.  This pipe has  walls 0.650 inch thick.

1500 grains in a 2 inch bore would not be excessive. Put it in a thin wall seamed low pressure pipe and all you have is a pipe bomb.  I would not get any where near this thing when it is fired.   It is only a matter of time before it blows.
 

[Cat Whisperer]

busadave -

Take heed - we DON'T want to read about this in the national news.

[Rickk]

ask your friend about his "pipe". Is it seamed pipe or seamless tubing? If is is seamed pipe you might want to point him to some of the discussions here about the use of seamed pipe. It may crack on the weld seam and hurt somebody. If it is seamless tubing, a second tube shrunk fit over the first one in the area of the "chamber" to bring the OD up to 6 inches or so would make it really safe.