Lighter side: my department gets in a lot of old ammo. We often shoot much of it in our indoor range. I gave a buddy 50 rounds of pretty old 38 probably in the 40yr old range. No idea how it was stored. Months later he calls me down to the range with a huge grin. He's a fellow LE firearms instructor with me, so I knew it had to be something good.
He loads his retired fathers 38 snubbie, aims, and pulls the trigger. Silence for about a 2 second count. He's still aiming the snubbie on target. Then the BOOM the round goes off. Something was up with them causing delayed ignition. First time I've ever seen it like that! 2 seconds is a long time.
Most I had seen before that was my fault when I loaded 300RUM 94grain of powder with a non magnum primer. delayed, but only a milisecond. These 38's felt like forever! Lesson is, if it doesn't go bang, make sure the muzzle is down range!