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View Full Version : Here comes the Concussion mortar.



displayfireworks1
02-17-2017, 09:28 PM
Ok, you got me talking about the A-B mixture in a prior post, so I bought a Thunder Mug, Concussion Mortar whatever you want to call it. It brings back some memories and gives me new pyro video material. Here is my unlisted video for the forums. I will eventually make a video for youtube subscribers. If one of the pyrotalk members has some knowledge of the strength of this metal used for this device please tell me. It weights around 3.7 pounds. Please review the data listed below.
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https://www.youtube.com/watch?v=XtTPuyn94-4
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It is made from 6061-T6 aluminum alloy. T6 temper 6061 has an ultimate tensile strength of at least 42,000 psi (300 MPa) and yield strength of at least 35,000 psi (241 MPa). More typical values are 45,000 psi (310 MPa) and 40,000 psi (275 MPa), respectively.
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The pictures below are from the Ebay ad.
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1891&stc=1
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1892&stc=1
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1893&stc=1
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1894&stc=1
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1895&stc=1

ras1986
02-18-2017, 12:01 AM
That aluminum is soft. Any drill will cut through it in seconds. You could fill that mug with flash and I don't think it will blow. 6061 t6 is a typical material used for extrusion shapes... it's semi hard, harder than 3003 or 4043 but not as hard as aircraft 7071

Bgreen
02-18-2017, 12:03 AM
Dave I was thinking couldn't you just load it all from the top ematch then a b mix and not have to drill?

Grumps
02-18-2017, 06:37 AM
Dave, the concussion pots I'm familiar with are made from steel and are about the same size as yours. There is no fuse hole, the ematch is brought in though the top all the way to the bottom of the pot and duct taped to the outside to stabilize it. Typically 1/4 to 1/2 of a bottle of the mixed A/B mixture is put into the pot, and two layers of duct tape is put over the top to confine the A/B mix. The steel pots do "wear out" after many shots due to corrosion and erosion due the to hot gases generated.

There is a significant difference in pressure levels and burn times between black powder and the A/B mix. The A/B mix produces much higher pressures much faster than black powder. Since your pot is made from aluminum, I would start by using maybe 5 grams of mix and one layer of tape, and never stuff wadding or a projectile in the bore if using the A/B mix. It would be interesting if you could take measurements of the outer diameter of the pot before and after use to see if changes.

displayfireworks1
02-18-2017, 11:31 AM
Thanks everyone for the comments. I could swear the ones I remember from years back had a side hole large enough to place an electric match into it. If you using an A/B mixture I can just place the match in position from the top. Maybe use a paper towel or tissue pushed into the hole to hold the match in place. When using black powder , probably not a good idea to place the match from the top and then pound in the paper with the match at the bottom. May be best to use fuse hole with the black powder. I was also thinking this mortar could be use to make a nice dragon breath using lycopodium powder.
I see one comment mentioning the device will change shape and enlarge if stressed too much. Curious if the 6061-T6 aluminum alloy would fail from too much pressure, how would it behave. Possible a stress crack, i am doubting it would shrapnel out. I am going to guess the designer picked this metal alloy for a reason.

ras1986
02-18-2017, 07:25 PM
The aluminum won't shrapnel like steel. It will rip for sure and turn into chunks. Since it's so soft I think it would just stretch out

displayfireworks1
02-18-2017, 09:46 PM
See, I am following the directions. Next stop, Boom Time.
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https://www.youtube.com/watch?v=yEYZkuEMd2s
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1901&stc=1
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1902&stc=1

displayfireworks1
02-20-2017, 09:47 AM
I was out shooting the Shogun fireworks sample demo and added in the mortar video. This is according to the directions supplied with the device.
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https://www.youtube.com/watch?v=ngoC8ZCzaME
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http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=1905&stc=1

displayfireworks1
03-01-2017, 08:01 PM
I received an update on the ebay seller of these mortars. He told me he now has a supplier of 1018 Steel for future mortars . Any opinion on this 1018 steel? I am eventually going to A/B mixture the mortar I purchased, just need to right venue. LOL

Grumps
03-02-2017, 08:16 AM
1018 steel is a mild/low carbon steel with the following mechanical specs: Tensile Strength, Ultimate 440 MPa (63800 psi):Tensile Strength, Yield 370 MPa (53700 psi). This material is significantly stronger than the 6061-T6 aluminum item you currently have.

The steel concussion pots I am familiar with are capable of using 1 ounce of A/B mix at a time. I don't know what steel was used to fabricate them, but I'd guess that it would be a 1XXX series steel.

displayfireworks1
03-30-2017, 06:03 PM
On my youtube friends sent me this video in response to my youtube teaser video. We now see some of their setup technique.
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https://www.youtube.com/watch?v=3aSEqjWansY&t=0s

CatSpit
03-30-2017, 09:32 PM
I have been shooting these for many years. They are legal in most states and if loaded correctly they can make a skull cracking boom that can break your neighbor’s windows. There is plenty of information on the net about “Thundermugs” the good and the bad. A word of caution, if these devices are heavily overloaded they will fragment and cause death or injury.
I have information on steel mug failures but I have yet to find any on aluminum due to the fact aluminum mugs came on market in the past year are so.
The biggest percentages of failures were due to the use of “Smokeless Powder” and next in line were under built mugs where the thickness of the walls was not adequate.

I have never been brave enough to load one of these with flash but many have successfully done so with fairly good results. One reason I chose not to is because of metal fatigue. To a very small degree every time your fire the mug, the barrel expands and retracts very slightly. Many can be fooled into thinking that the barrel can handle a massive load after successfully firing the mug without it blowing apart. They may do this 5,10,20 times with a overloaded charge and become comfortable. But that one time your mug turns into a pipe bomb mowing down bystanders, is not a chance I’m willing to take.

Everyone will give advice on how to load your mug. But after years of shooting I have found what gives me the loudest report… and I do mean loud!
The loudest mug I own has a 2” bore and I use a 960 grain charge of FFF black powder. I use a golf ball size of modeling clay between 2 - 2” cardboard discs as the wadding and gently tap the wad into place with a wooden 2” dowel. This seals perfectly for short barreled 2” mugs. The wadding I use for anything under 1.5” bore is simply 1 – 1.5” cardboard disk and 1 slice of white bread gently tapped into place.

The photo I have provided is one of the custom mugs I had made. Lots of fun.

150 caliber salute cannon custom machined. 12 inches of polished 1018 steel with a massive 1.5” x 10” bore polished all they way down to the breech. This beast weighs in just over 80lbs. Over spec. exceeding American Artillery Association’s safety standards.
http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=2036&stc=1
http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=2037&stc=1

displayfireworks1
03-31-2017, 07:05 AM
One of those mortars I have is made of aluminum. The golf ball one is steel. Someone that follows my video and has an engineering background told me to measure the device from time to time and look for changes. I like the looks of that one you have. In the above video I posted, I wonder what material they use to make their mortars. Also, it would be interesting to know the composition of the powder they use to make the noise and also the powder for the ground fuse.

nayslayer
03-31-2017, 09:21 AM
wow thats great

joewad
04-04-2017, 06:36 PM
interesting a can of beer is used as a reference, a cheap domestic at that

PyroManiacs
04-04-2017, 07:58 PM
The photo I have provided is one of the custom mugs I had made. Lots of fun.

150 caliber salute cannon custom machined. 12 inches of polished 1018 steel with a massive 1.5” x 10” bore polished all they way down to the breech. This beast weighs in just over 80lbs. Over spec. exceeding American Artillery Association’s safety standards.
http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=2036&stc=1
http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=2037&stc=1

I totally want one of these ones!

CatSpit
04-11-2017, 07:31 PM
Here is the loudest of the 2” bore mugs I own. Goes by the name of “Big Daddy” Made from1144 Stressproof steel and retails for about $120.00
For measuring powder I use a plastic 35mm film can. For FFF 1 can full is about 30.9 grams or 477 grains. I have always had the loudest report using 1 film can full to 1” of bore diameter so with this mug I use 2 full cans. I pack the bore with thick cardboard discs and then a chunk of soft modeling clay and another cardboard disc gently tapped into place. I have fired this mug side by side with all the others. It is defiantly a clear winner.
http://www.pyrotalk.com/bulletin/attachment.php?attachmentid=2082&stc=1

Kenny East
04-18-2017, 06:20 AM
I've got a few small salute cannons from kershaw, but their scaled down versions of full size cannons... .50 cal. But they have quite a bark... Found a 12ga blank firing Cannon for sale a few weeks back... Only problem was it was missing it's breechblock... So it couldn't shoot... Maybe if i only had a lathe or mill to make a new breechblock... Love the tissue used in the a/b load... Did a similar thing while explaining the difference between bp,whisle mix, and flash for my wife