Product Overview 50 Round polymer Drum Magazine by KCI. The .40 cal 50 Round Drum (Mag) is very easy loading using the side ratchet system to make it painless to put all 50 rounds in without any tension. Reviews (1 review) Write a Review 1 Review Hide Reviews Show Reviews 5 Cal. .40 Drum Magazine Posted by Unknown on 31st Jan 2022 Fine product - operates well - I would buy it again ! Everything okay!