I took my new AAC Ti-rant can out today for the first time and now when I shake it small black flakes come out. It's not burnt powder, but I'm not really sure what it is? Is this normal? I was shooting Copper plated bullets, and the manual only mentioned exposed lead being a no-no. My second question is do people use Hollow points in a suppressor? The manual clearly states you shouldn't use any ammo with exposed lead?