wow that's incredibly dangerous way to go about doing it..
What we did in highschool is pretty much the same, except We used a base, in which the bottle was attached, and held down via two pins across the neck of the bottle..
Then when we got it to the desired pressure, we'd take a rope connected to the pins and yank them off, and of course the base would need to be properly anchored so that it doesn't shift and end up pointing at you..
You can also get a greater pressure than you can doing it through that link.. and there's not much risk of it exploding the bottle, as they are very strong, but if you pump enough pressure, it will explode water, and generally no pieced of plastic or parts would fly anywhere, but always make sure to be wearing proper apparel
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