Blast chamber

[warren]

Hey, I live in the city and there are soccer moms all around and they will be on the phone in no time if they even hear a firecracker (I live in Canada there illegal). It is also winter and I don't feel like going all the way out to my blast site to light off small AP salutes or cobs, M-80's and the like so if someone could help me out or give me tips on how-to make a blast chamber that would reduce sound it would be appreciated. I searched google and only found how to make big blast chambers and blast chambers for heating things up (like knives and swords).

[Haggis]

A high quality containment device can be made by several old tires stacked on each other buried underground. Such a device would need a lid, and plywood with a cinderblock or similar on top would suffice. The tires are quite tough, and can take some punishment.

Another chamber, although less effective, is a few cinderblocks stacked ontop of eachother underground. As with the tire, it must have a lid.

The cinderblock is inferior to the tires as the tires have areas in which the noise and gases get trapped. Also the rubber can give slightly where the cinderblock may and will crack. If using the cinderblock idea, proper tamping is a must. Make sure there is no room between the outer wall of the block and the dirt outside, this will give the pressure a way to go, and will increase your likelyhood of cracking. Tires are optimal if you can do it.

Another option is simply burying it. A 7 gram flash salute, when under around 12 inches of soft soil, turns out to a thump and a cloud of dirt in the air.

[knowledgehungry]

What I use is a 5 gallon pail filled with sand, 3 grams of AP makes no noise. you can use sand bags as insulation for a bigger box too.

[Anthony]

One idea is a 45/55 gallon drum buried in the ground with a concrete filled tyre as a lid.

[Bert]

Or you could take up ice fishing. Just don't hang out too close to the hole.