Dead Powerlet

A funny thing happened today. I was test firing a Gamo P-25 .177 that I have modified with an 11" barrel.

I loaded a fresh Crosman Powerlet with no loss of gas. First shot nothing happened except for a hammer drop. Same for the second shot.

When I ejected the cylinder it was dead - no hiss. Pierced but empty. Looks like the Powerlet was a dud. Has this happened to anyone else?