If you still can't get the charge to fire after putting the new nipple and a few grains of loose powder in, you're going to either have to pull the sabot out via a screw-in jag, or the better method is to buy a C02 unloader, which fits on the nipple and you squirt some CO2 through to push the whole load out. If you end up going that route, just be careful because it does come out with some force. Do it outside pointing at some soft ground. Good luck.