Probably get sent to the FAQs for this but here goes. I ran across three different new 357 sb1 clean barrels last week at three different shops. I thought and must have been wrong but the barrels looked a lot smaller than the 44 mag barrels. I thought they were same diameter with smaller bore. They almost looked like superlight barrels to me. Needing an excuse to go back anyways. Didn't hit me on the first one, something seemed a bit off on the second one, and the third I said LET ME SEE THAT. Wasn't interested cause of sb1 but it sure seemed a lot different to me. If I ever get a barrel and it is that slender, I'll be happy.