Yes, we are aware of The Artilleryman article, and for years Mike and I both thought that almost all cannon characters were engraved, that is, until we actually experimented and duplicated simple, medium and very complex characters including naval anchors, etc. using a variety of STAMPING punches and dies. We use hand tools, hydraulic powered multiple character dies and other special dies which are proprietary. You can, however, do a very fine job with hand stamps, especially large ones like the 1/2 mentioned which are much, much easier to align than the smaller sizes like .040" or .060". The most important technique comes from our gunsmith training and it is every bit as important as the carpenter's golden rule which is "Measure twice; cut once". For accurate hand stamping you MUST select a hammer at least twice as heavy as you first think necessary for the job and use only moderate hammer blows for excellent control. If you use a light hammer with heavy or violent blows, you will have no acceptable degree of control. We use a 24 oz. ball peen on the large radius side for standard 1/8" stamps. The second technique for cutting deep impressions is to use a heavy hammer with moderate to light blows and to "advance" or rotate the striking end of the stamp about 10 degrees with each blow, and then repeat the process, rotating in the opposite direction WITHOUT REMOVING THE STAMP FROM THE IMPRESSION until the correct depth is reached. You must remove all "raised material" from your impression with a fine file, and polish the surface with a hard surface sanding block, no rubber blocks, please.
You can compare original impressions made 150 years ago and some made by us using the stamping process by simply looking at the photo gallery labeled "Details" on our website via the banner above this board's home page. Good luck.
Regards,
Mike and Tracy