Winchester has had some serious problems lately. Several blown up Rifles from use of wrong powder in ammunition resulting in a recall.
Winchester 5.56 Ammunition Recall | The Firearm Blog
While this recall was for 5.56mm (.223) ammo, it could happen in any part of their manufacturing operation. The same poor quality control that allows someone to load a machine with "Pistol" powder can also allow improperly assembled rounds to make it out the door.
That's why I prefer to make my own. Rather than buy New ammo, I just buy new cases and assemble my own when I want something other than a "reload".
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