Unless they have an incredible excess of piss.
How to make a Quassam 'missile' (bottle-rocket):
Take one big metal tube.
Pack it full of sugar, and potassium nitrate, and put some big firecrackers (equivalent to four M80's) in the tip.
(recipe for potassium nitrate from the Wiki):
Historically, nitre-beds were prepared by mixing manure with either mortar or wood ashes, common earth and organic materials such as straw to give porosity to a compost pile typically 1.5 meters high by 2 meters wide by 5 meters long.[3] The heap was usually under a cover from the rain, kept moist with urine, turned often to accelerate the decomposition and leached with water after approximately one year. The liquid containing various nitrates was then converted with wood ashes to potassium nitrates, crystallized and refined for use in gunpowder.
I suspect the Gazans just used more pissers to cut the time down.
Not much chance of stopping the availability of pipes, piss, or sugar, is there?
I suggest that there might be an "Otro Modo" to be found here.
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