Both of the .44's that you mention should have throats that will mic out at .432"-.433", while all .44 bullets will run .429" -.430" for jacketed, and up to .431" for cast lead. Smith didn't tighten them until about late 1989.

They have even used undersized thoats on some of their guns made back in the early 1990's, such as the Magna Classic series. Those generally run around .428". How Smith got them to shoot so well with undersized throats is a bit of a mystery, but those were the most accuarate guns Smith has produced. Obviously, they were .44 magnums, and that round builds enough pressure to cause the bullet to slug back up once it hits the resistance of the rifling, making them fit snug in the bore after being swaged down by the undersized throats. I have an excellent article on PDF that I have sent to a lot of guys who are interested in the model 29, and its various changes over the years. In it, there is a small discussion about the undersized throats. I would be glad to send it to anyone who wants it. Just send me an e-mail asking for it.