I found this at the Henryville Range

[j706]

I am betting those things were hell on barrel throats.

 

[JTScribe]

What, .22's just make TOO big a hole?

 

[Indy-Mike]

Interview with Bill Eichelberger on the “Extreme Small Calibers”. Bill Eichelberger is probably the go-to guy, the guru, the authority on the small calibers. His experimentation with the .14’s, .12’s and .10’s has been extensive, and I would like to thank him for this effort and recognize him for the work that he has done.

Saubier.com