Welcome to Guntalk-Online! Sorry about your latest experience.
What you had there was an out-of-battery detonation. Basically the cartridge case wasn't fully inserted in the chamber when it detonated and the case ruptured. It happens from time to time but is not all that common. You're about the fourth one I've heard about in the last two years. Basically the cartridge case would have look like this (if it had stayed together) -
Instead what you ended up with was a case separation like this one.
The results of the lower one is exactly like you described. I know you have a case stuck in the chamber, but did the bullet exit the barrel?
A dirty/fouled chamber, an improperly tight fit with the LCI, or a damaged disconnector would be the likely suspects. What ammo were you shooting? (I hope it wasn't Remington's) Is the piece of brass case still stuck in the chamber? Like in the lower picture, how much of the case was lost to the detonation? You can take the piece, if you still have it and match it up like the second photo does to see how much case was lost. The missing parts can be replaced by you, rather than sending it in to Ruger. If you did send it in then you would want to replace all the custom parts with the originals.
Look at the disconnector. Is is smoothly shaped on the top edge, or does it look dented like this one?
If the disconnector is damaged then a trip to Ruger is necessary, as these are controlled parts and they won't send you a new one.
Once you get the case out of the chamber, you can inspect it for any leading or excessive powder residue. Drop check some rounds into the chamber to see if they fit smoothly.
If no lead or disconnector damage then the next likely suspect would be the metal tab on the LCI. Unfortunately you won't be able to check that out since it was blown from the pistol.
I'm curious to hear what you discover after inspecting your pistol.
R,
Bullseye