Interesting advertisement in 1896 for Greener’s Wrought Steel “Indestructible by Gunpowder”. I don't know the process or composition. It was not part of the 1891 Proof House Trial report, but Whitworth's and several other English steels were
https://docs.google.com/document/d/1cvqRzkg0wEjhAAcFWr8gFi7aPFRsSIJ_hahfDxmrNAU/edit

[Linked Image from photos.smugmug.com]

The Gun and Its Development, 8th Edition, 1907 he appears to have joined the fluid compressed steel fan club.
http://books.google.com/books?id=3HMCAAAAYAAJ
Owing to the great difficulty in procuring perfectly welded barrels, gun-makers are now discarding tubes of the Damascus variety for those of solid steel which are free from greys and blemishes, and if carefully chosen and tested will fill every requirement of the sportsman; in fact, guns of every quality, from the cheapest to the best, are being fitted with barrels made from one or another of the numerous brands of steel available. The harder the Damascus barrel the greater the liability to “greys,” and a soft barrel will not make a fine shooting gun. Of the steels used for shotgun barrels, the best known is Whitworth's fluid compressed steel.
This is a cast steel; the ingot whilst in a liquid or a semi-liquid state is submitted to pressure, with a view to eliminating blow-holes. The top and bottom of the ingot is cut off and thrown aside as usual. Eminent metallurgists contend that in the process of cooling the contraction of the ingot is so great that no pressure which can be brought to act upon it by mechanical means can affect the metal — at any rate, beyond a few inches from the surface. The process is therefore by some regarded as quite superfluous. On the other hand, it is generally allowed that the Whitworth steel is of excellent quality, and it has been used for barrels for so many years that its suitability for that purpose may be taken as fully proven.[/quote]


amongst my holdings, i have an orphaned set of greener's wrought steel barrels, always been a bit curious, but there's not a lot of information regarding them....40,000 serial number range puts them in 1896 or so.

best regards,

tom

"it's a poor sort of memory that only works backwards."
lewis carroll, Alice in Wonderland