An 1899 in .38-55 was one of my grail guns. It's pretty rare since they stopped chambering for it in 1914, along with the .32-40 and 25-35. I was lucky enough to find an 1899 takedown in .38-55 while on vacation in Wisconsin a few years ago. It was in a small shop in Superior and when I saw it in the rack I figured it was in a caliber I already had. So I looked at the tag and couldn't believe my eyes, a .38-55. My heart started to pound 'cause I figured I couldn't afford it. I looked at the price and asked the clerk if that was correct! Yup he said, $400!! Out the door with me it went me. Bore was in great shape, over all good condition. LGS said he can't sell guns if Walmart dosen't have ammo for them!! Good for me!!
Anyhow, it shoots great, 10 grains of Unique, same load I shoot in the Marlin!!
Just to make you feel better, it's not the octagon barrel!! Just keep looking, the hunt is the fun part. Good Luck!!