Charles, what is the serial number and is it a hammer gun?
If a hammer gun from 1895 it would have a 5 pin bar action lock, meaning the mainspring is before the tumbler or action. It could have Royal steel barrels or Best English Stub Twist if it is an F grade. The top tang would be stepped.
From 1920 it would be a two pin back action lock meaning the mainspring is behind the tumbler and by now would only have Royal Steel barrels and should have an "H" as a prefix before the serial number. The top tang would be tapered.