Pete,
I am relatively new to using/collecting Bakers. However, I currently own and have used a B grade and a Paragon grade, with twist and damascus barrels respectively, for three years. The barrels on both guns are very thick at the breech and thicker than most modern steel barrels at the muzzle. According to knowlegeable experts(Darryl Hallquist and James Tyson)both guns were manufactured in the first decade of the 20th century. I have shot both guns without problems. I use either low pressure smokeless powder shells or Black Powder shells.
I am newly registered on this site but have browsed this forum for years and I remember that not too long ago someone on this forum blew up the right barrel on a Baker A grade with Smokeless powder. I am biased I suppose but the pictures of the shells he had shot showed brass heads heavily deformed after firing, suggesting these reloaded shells had been overloaded.
If you are looking for high grade Baker guns, Greg Martin Auctions is having an auction sale in June with a presentation grade Baker and eight or nine Paragon grades, along with about the same number of A, B and R grades. you can view these guns at http://www.gregmartinauctions.com.
I have a feeling Bakers are becoming more well known. Houchins talks about Bakers and praises the guns(the earliest hammer guns through the last generation of hammerless guns built by H&D Folsom) in his book on L.C. Smith guns that was just published recently.
I hope everything goes well for you and I hope those of us who like Bakers keep in touch. I know I would like to learn more about the man and the company that bore his name.
Joe