Battle, I think it was the amount of time he left the barrels soaking in acid. frown
My Parker barrels were etched so severely that the rib engraving almost disappeared and the serial number on the side of the underlug is almost unreadable. Best of all was the etch was allowed to do its work inside the entire length of the bores! My gunsmith had his work cut out trying to hone them out for me.

When an old man dies a library burns to the ground. (Old African proverb)