Sorry I took so long to get back., but a few things required my attention. I`m glad I asked the question as I am learning a lot from the replies of knowledgeable members. I need to be clear about the swamp. I am thinking of only a very slight swamp, something you might need a micrometer to detect. Many such barrels were made. My two reasons for doing it are easier inletting because of the small variation in thickness, and just the satisfaction of having done it. I have never inletted a barrel before, and inletting for a swamped barrel is the part of building that looks to be the most difficult.
It now appears as if buying a swamped barrel makes more sense with the relatively small difference in price. I want to carve the stock from a blank. I know I will not be happy with my first attempt, and so I will buy two stock blanks, the first of cheap ash on which I can make my beginners mistakes, and the second of grade 2 or 3 curly maple which I will use on the rifle. It will probably be sometime this fall before I start. Thank you one and all. This has really been informative.
Regards,
MR