Actually, A. Hollis and Son were of Mincing Lane and an earlier address with a Royal warrant from the Duke of Connaught, London.
Once again I don't wish to start a pissing match, but a statement of Krupp barrels excluding Leonard is a bit over the top. Leonard supplied to the trades. That's why my A. Hollis looks just like a W.J. Jeffery of the period. They were supplied by the same firm!
I'm sure your friend is most sincere his affection for double rifle.
I can only atest to what I have personally seen handled and learned from folks like 400 Nitro Express, George Caswell of Champlin Firearms, NE 450#2 and others.
-------------------- Rusty
We band of brothers! DRSS