TUK101, that looks like the hollow point sierra to me,I'd expect them to open up quiet well at 30-30 volicity. I feel they are as light as I want in 30/06 cause the deer I've shot with them never took another step.
You may get some critical replies to your post because many people don't know the 340 is a bolt action with a clip instead of a tube mag.
Some of those rifles were really accurate and you may have one of them, but you'll likely need to scope it to find out.