I just purchased a NAA Black Widow model NAA-BWM, 22 mag to add to my collection. Thought it might be a fun little gun to plink with at the range, or possibly a nice little backup to my EDC. Included in the box was a notice telling me not to use Armscor Precision or PMC ammo, both Magnum or LR, for fear of double-discharge. I'm a retired electronics guy, not a machinist, but I do understand the basics of how a revolver works. Thus, I can't see how this could happen. The hammer comes down on the outside edge of that rim and it goes bang! How could that also fire another round in another chamber? With my Pietta black powder cap and ball revolver sure... several ways the flash from one chamber could reach the powder in another one if not loaded correctly. However, fail to see how this could happen in a modern revolver regardless of what brand round. Can somebody with more knowledge about this enlighten me please?