Murphy's Law relates his reloading mishap as an important lesson to always check your cases while loading.
My great reloading folly occurred out of a combination of ignorance and reliance upon another.
This occurred back in the early '90s when I was a newly minted shooter in Toronto.
Having been a member of the local gun range for two years and having already received permission by the police to buy a .22 pistol a year before, I was ready to move beyond owning a .22 to something with a bit more oomph.
I went out and bought a beautiful used Smith and Wesson Model 29-2 4" .44 magnum from a more senior club member, who also graciously sold me reloads for it. The range was strictly lead bullet only, no jacketed ammo at all so it was reload or reload, your choice.
After buying reloads from him for awhile, I then went out and bought an RCBS Partner press kit, some 44 Magnum dies and entered the fun world of reloading.
That's where Dan came in. A buddy of mine, he was interested in shooting and professed he possessed far more knowledge than as it turns out he really had at the time.
I had about 100 rounds of empty fired brass and he offered to clean it for me before we reloaded it, and he assured me that he knew what he was doing.
Sure enough the cases came back sparklingly clean.
Together we carefully loaded them with 20 grains of 2400 behind a 240 grain LSWC, weighing every powder charge and being exceedingly careful. The cartridges looked perfect and had been loaded perfectly.
We then proudly take them to the range. Now 20 grains of 2400 is a kickingly good load with lots of sound and fury. In my 29-2 it was also an exceedingly accurate load, capable of clover-leafing all 5 shots at 25 yards, so we were ready for some fun.
The first round was fired - whooooosh---then---bang! That didn't sound right. We checked the barrel for any hangups and moved on.
The second round was similarly a delayed ignition with sparks actually visible as it fired. Again, we checked the barrel for any hangups and moved on.
The third round was similarly so slow that standing behind the gun you could actually see the bullet slowly moving towards the target.
What the heck?
It turned out that Dan had cleaned the cartridges all right - in the closed silverware case in a dishwasher. He then dried them in his oven - enough that no moisture was readily visible but still not dried enough.
We had unintentionally created the first ultra-subsonic .44 Magnum load.
This is why you keep your powder dry.
And also why you don't rely on other people's helpful offers to take your cases and clean them for you.
From that day forth, all reloading was done at my place under my supervision and no further wet powder charges ever occurred.