Royal Nonesuch, a home-made firearms YouTuber has continued to sink to lower lows of safety (although some may argue increases in ingenuity) through his various homemade firearms projects. The latest project show is a .50 Cal firing through a pipe.
A preliminary analysis shows that this should have catastrophically failed (especially if the bullet had any resistance in the bore increasing pressure). If anything, this kid was lucky that this did not grenade and fragment. That pipe is not rated for the pressures of a detonation, even without additional pressure in the bore.
At the rate this guy is going, he really is going to put one of his own eyes out. For anyone with any common sense, DO NOT DO THIS AT HOME.