Is this normal? I just purchased my first Leica (M7) along with a 50mm/f2 Summicron. The lens is used but good condition. When I went to mount it I noticed that the rear brass inner barrel appears to be chipped right where the bayonet curves down. Iíve attached a photo below. The chip follows the bayonet curve so closely that Iím second-guessing myself as to whether this is correct or not. Can someone take a look at the back of their lens to see if the brass inner barrel looks like this?