Take a proper rod and knock the round out.
Do not let Sig off the hook. I am a huge Sig fan but a broken gun right out of the box is unacceptable.
Send it back give them one more chance to make it right. If they cannot do that then ask for a check directly from Sig.
-The right to be left alone is the most comprehensive of rights, and the right most valued by free people.-Louis Brandeis
-Its a tool box... I don't care you put the tools in for the job that's all... -Sam from Ronin
-It is the mark of an educated mind to be able to entertain a thought without accepting it. -Aristotle