A light charge of powder as said above should blow it out . However once you get some powder in , make sure the jag is seated .
If you cant get that to work .
If you don’t have one already I would pick up a C02 discharger . This fits over the nipple and will most times blow the ball or obstruction out .
Now I have been told that bicycle shops sell a C02 tier inflator that also works well though I have not tried it
If its really stubborn and the discharger will not blow it then take it to your air compressor . Use the air nozzle type , the one with a rubber nose and has a trigger to clean items by blowing air .
Take the tipple off and hold this as tight as you can with the gun pointed in a safe direction. Give her a blast .
If its really , really stuck you can get a grease fitting and thread it in place of the nipple and pump it out with grease .
Some will recommend to pull the breech plug and push it out . I wouldn’t recommend this with a CVA .
Reason CVA seated their plug under pressure and while its not impossible to get them out , most times it not easy .
Top that off with the great possibility that the drum may thread into the breech face itself . On some rifles they did this as well . So you may have to pull the drum bolster as well . This also can be complicated as CVA used two different designed necks on the drum bolsters . One with a short neck stopping at the breech face and one that went all the way through the bore , sealing on the far side and having a flash hole drilled in the side to allow the powder to be ignited ..
So basically if one doesn’t understand the differences in manufacturing they can have a good chance of really mucking the job up .
My bet is the first two salutations will make quick work of the situation
is it a brush that down their or a jag?.
You might get lucky and it will blow out . If you had a cleaning patch on the brush or maybe an over sized brush that fit the bore tight you may get lucky .
a brush can be a real pain to get out especially if you were twisting it or its a spiral wrapped brush ..
With a brush my first sugestion would be to try to get a wire loop down around the broken end of the RR . If your real lucky you can get enough pressure pulling to turn the bush wires . This is whats holding it down their .
If this dose not work , take the barrel off the rifle and go down to the hardware store and find a screen door spring that will fit into the bore . Make sure its long now , as long as you can get . Take this home and stretch it out so the coils are ¼ inch apart . Now thread this down the bore . It will thread its way through the brush . When this happens start pulling . This will most times compress the bristles enough for you to pull it out . If your real lucky the brush will come out with the spring coil .
Past that and I would only recommend it as a last resort is to pull the breech plug , take a wood dowel and push it out .
If it’s a jag