I had a Black Diamond a while back, had the same problem. I tried the T/C scope cover, it helped some but the front base and ring and the little bit of scope it didn't cover still got scorched and caked with crud. I was only using CCI musket caps also. Also tried the T/C breech cover and it was basically useless for scope protection, the front of it would raise up when the gun was fired allowing blowback out. The breech cover works for keeping moisture out of the breech area though. I finally solved my problem by just trading the Black Diamond for an Omega. No more scope burning problems now!