Hi Jeremy,
Arthur Howell & Co. used a similar stamp.
A.H&Co
Redoak
That is very interesting information; I shall have to check the details when I next get a chance.
I don't recall the underlining of the small o. However, in view of your post, I am much more inclined to think that what I have is in fact a A Howell & Co stamped set of barrels. I've long been suspicious that Armstrong & Co had any real in house gunsmithing capability. They seem to have been much more of a Sporting Goods store putting their name on a wide range of items including golf clubs and tennis rackets. I even have Maling pottery items from them which I find very odd. Perhaps they were retailed as picnic items??
thanks
Jeremy