The only way to accomplish what they attempted would be to use all plastic, including the cartridge case and bullet. While plastic cartridge cases for rifle rounds have been developed, and while under the right circumstances, I think a plastic round could be made and it would even do the job, attempting to use it would lead to loss of whatever hand was holding it.
It wouldn't even really work once. Well, I suppose if you were holding it up close and personal, it might, the whole thing would simply blow up when the primer ignited the powder.
Remember that when you fire a round, the brass of the case expands to fill the chamber, which is why brass has to be resized for reloading. Expanding inside a plastic chamber, there would be nothing to limit how far it could expand.
Ultimately, if it launched the round, which I'm not sure it would, the gun would remove several fingers, if not your hand.
Not to mention, the plastic shrapnel would be launched into other body parts.
That might do the job of igniting the primer, but then it would be launched back into you!