Winchester specs .357"Bullet diameter on the Legend is .357, not .355. Like I said- it's basically a rimless 357 Maximum. Here's a link to the Winchester site with dimensions on the Legend. https://winchester.com/350-legend/faq
Others spec .355" including the first people to chamber the round.
Nice mess eh ?
Here is a link that might help explain the mess.
What's Going On With .350 Legend? - The Truth About Guns
I’ve been asked a lot about the new .350 Legend cartridge, the round that’s set to take on the .450 Bushmaster in the straight-wall legal midwest woods. The .350 Legend has a number of great advantages, and it’s gotten a very positive reception. But there are questions about the cartridge that...
www.thetruthaboutguns.com