its a tip, jag and patch. there is no load under the jag
Then a CO2 discharger should work. (I got mine from Cabelas)
If one's not handy, you could try sending a patch worm down on a field rod and try to snag the edges of the patch. First clean the bore from the jag back to the muzzle to reduce friction. Then if you can get ahold of the patch edges, you may be able to pull the whole mess out.
Or, if the ramrod was a wooden one, there may be enough wood inside the tip where you could screw a ball-puller screw into the wood, and pull it out.
Short of unbreeching, those are the ideas I can think of.