That's very strange. Are you sure the mags are pushing the BBs into the loading tube? Because if you have a half-@$$ed spring in your mag that kinda half-pushes the BBs in, those get jammed. Check the BBs that fall out for signs of wear (E.G. Chips, dents, cracks, etc.) because that's a telltale sign that something's misaligned, whether the BB or some internal part(s).
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