I've used the 180 .311 Sierra in various 303's since 1965. They don't appear to have changed any over the years and always performed well. 4350 is tough to beat for bullets 180 and heavier. In a Ruger, you about can't overload it.
The vertical stringing in Ruger Number ones is almost always due to improper forarm pressure and/or fit. A lightened hammer or a lighter replacement also helps. GD
