The barrel Drew pictured are a set I own and they are not the same as the Vickers barrels that Atlas sold. Atlas also offered barrels fitted, I think they were sourced or fitted in Belgium. The barrel pictured is much higher quality than the Vickers barrels, I have seen several of the Vickers and they are pretty crude.

I learn something every day, and a lot of times it's that what I learned the day before was wrong