storage.googleapis.com · 2018. 7. 24. · 7. M4 feed ramps. M4 feed ramps are cut into the barrel...
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storage.googleapis.com · 2018. 7. 24. · 7. M4 feed ramps. M4 feed ramps are cut into the barrel extension and matched to feed ramps cut into the up- per receiver. Longer, heavier
