What was my mistake?

[Mogadishu Meanderer]

All of the responses are just speculation and as such all can be correct -- pick which one you like

I would not probably do that. Pick the one that makes sense!

 

[hawkeye2]

First off, NO FIREARM, REGARDLESS OF IGNITION SHOULD BE CALLED A "TOY"
These are all dangerous if not respected
As to what happened, I would go with no powder , and from the view I would say the cylinder could not revolve to the nest firing position with the ball partially in the barrel

Since it's a Remington copy the cylinder couldn't be removed if the ball was in such a position as to block rotation. It would have to be driven back into the cylinder to allow the cylinder to be removed. Colt, no problem.

No chance of a ball being oversize as the chamber cuts it down to size as it's loaded.

 

[smoothshooter]

Today, I had a major uh oh moment. Let me begin by saying ive shot black powder for years with no issues, but mostly muskets. Ive shot a lot of revolvers but mainly blanks in reenacting. Today I loaded my new toy a 1858 remington. I began by loading 30 grains of powder, my ball, packed the ball, and put muzzleloading grease over the top of the cylinder. First round of shots went great, reloaded shot once...no issue...the second time made a noise that didnt sound right. I popped out the cylinder and to my suprise the ball was lodged in the throat of the barrel! Had I pulled another round im afraid this gun would have exploded in my hands. Any idea what I done wrong? Thanks

Indon’t know if the gun would have “ exploded “‘ but you would very likely gotten a big dog knot in the barrel.

 

[Bad Karma]

I could have not but maybe too little as well. If I would have pulled the trigger agaim would it have exploded?

There’s a fairly good vent at the cylinder/barrel gap. I seriously doubt it would blow up or even bulge the barrel. Dixie Gun Works plugged the bore in a flintlock pistol barrel and ignited the charge. It apparently vented pressure through the vent only. If there’s an opening for the pressure to escape, it will take it. Edit: as that’s a brass frame I expect it would have stretched the frame or cracked it.
All that being said, it a good idea to establish a methodical loading process and check yourself. There’s no sense tempting fate.

 

[DixieTexian]

Could have been a bit of water in the chamber before loading.

 

[springfield art]

A friend has a Remington .44 revolver. His target load is 25 gr FFFg, cornmeal filler and a .454 roundball. That loads to the top of the chamber. On the other side, I use 15 gr FFFg, a wonderwad and a .451 round ball. It loads lower in the chamber. He has won competitions with his revolver after having all the chambers made equal.
Back to your statement, even a minor distraction will cause you to skip a step in the loading process. Dryball happens to almost every bp shooter.

Much like shooting a ramrod out! We've all done it, glad this guy was OK.