Having a little problem getting rid of a very small piece of lead right at the second drive band on one half of the mould. I tried brushing it off with a cloth while still up to temperature and it didn't work. I tried a toothpick and the same. Being a brass mould I didn't want to try anything sharp for fear of scratching it. Any suggestions as it's leaving a mark on the bullets like there was trash in the mix when it's not, it's coming form this stuck on small piece of lead.