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Most barrel obstructions, and usually boolit/powder loads, can be cleared from a barrel via the use of a CO2 ball Discharge tool, pressed hard into the rear of the breechplug into the flash hole/channel.
Barring that, you really should concentrate on removing/neutralizing any possible load in the barrel - which can be very dangerous, if not fatal, should it accidently discharge from a tool spark.
If I had it in my hands, I would immerse the entire rear section of the gun (preferrably the entire rifle, laid in a trough) in a deep pail of kerosene (from any Hess gas station or hardware store), pouring the barrel full with it (if upended).
After soaking in the kero for a few days (minimum), any powder inside the load (?) should be wet enough to be safe to fiddle more with.
It's normal to insert a wire into the rear of the breechplug, and have it stop when it hits the internal transition from the (relatively) large primer hole to the much finer flash hole in the front end of the breechplug - BUT, if there's no load or other obstruction, you should be able to see a tiny pinpoint of light through the flash hole.
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