I have found that the WC ETM mags do not stand up to the test of time. They have a tendency to spread the feed lips at the case rim. This leads to feed problems. Granted, WC sent me 12 new magazines which wall sit new in original packaging. WC also suggested I try the Chip McCormick RPM mags so I purchase 3. They work great as do my recent purchase of Tripp Research magazines. For IDPA/USPSA shooting I recommend the CM or TR magazines.
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