If you mean on an empty chamber then I can give you a reason. From what I understand the extractor can impact the rim of the barrel and if done enough times can break the extractor. I have heard it can also adversly effect your trigger pull. A few times will not hurt but I would not make it a habit. Hope that helps :]
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Men sleep safe in there beds at night because rough men stand ready to do violence on their behalf.
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Men sleep safe in there beds at night because rough men stand ready to do violence on their behalf.