Worse case scenario I have had to correct.
1. Remove most of the broken and jammed bits of various rod material owner used and broke while trying to tap case out.
2. Remove barrel from upper, drill out bottom of damaged and punched through case head, carefully insert a screw extractor and use a BFH to whack on Tap Handle and drive the remains of the case free of the chamber.
3. Remove rest of material jammed into barrel bore, clean and scour bore and chamber, lap barrel to reduce scratches left by materials jammed into barrel bore.
4. Reassemble everything and test fire.
Best case scenario
1. Stand upper muzzle up and fill bore with a good penetrating oil, about 2 ounces of oil is all that is needed, I like KROIL Oil for this, let soak for about 20 minutes.
2. Insert solid brass rod turned to .224 diameter into bore
3. Tap rod sharply, hydraulic pressure of the oil forces the stuck case out.
4. This won't work if you have punched through the bottom of the case trying to drive it out with a too small rod plus if you do drive the case out it sometimes becomes hopelessly stuck on the rod.
Best prevention method.
Keep a one piece rod and oil in your shooting kit.
If a case becomes stuck at the range, drizzle a bit of oil down the muzzle and use the rod to tap the case free.
Stuck cases are usually much easier to pop free while the rifle is still hot and the metals are expanded.
Once the rifle chamber walls and the cartridge case cool and contract they tend to stick to each other like high quality glue.HTH