Another factoid to add. I have an early James Woodward "Automatic" SLNE. It has been sleeved and I had assumed that the original barrels were Damascus. I queried Purdey where the Woodward records reside. They say my gun gun was made in 1880 and orignally had steel barrels. So not only did Purdey and Woodward set the trend for the shape of lock plates they also were early users of steel barrels.

John Vibber
author of "Kingdom Come: A North Country Mystery"
available at amazon.come