I know a guy that had something similar happen to him. He was shooting skeet, H1, and upon the target breaking he felt a sting on his nose; there was just a few drops of blood and a little soreness.

A few days later, it was sore, kind of like pimple. He looked in the mirror and poked at it, and "tink", a pellet dropped into the sink!

And again, there were no other ranges in use.

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