I have that book by Klups and another Schiffer book on double rifles. They are some good books for quantifying the nature of drillings with good and lesser qualities described within. You might be able to decide what you want to buy after reading. But what I want and what I can buy are two different things. Good reading to you. Be Well, RZ.

Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy. Its inherent virtue is the equal sharing of misery. Winston Churchill.