Kind of difficult to explain without showing...Assuming the bottom is plastic...there are 4 tabs on the plastic bottom, 2 on each side, that fit into slots in the metal on the sides of the magazine...there is also a tab in the rear of the magazine. I use a thin butter knife...wife does not like that...slide it between the plastic and metal and twist outward. Once the tabs on one side disengage the rest is easy.
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