That barrel length won't be an issue.
A generic load that isn't too stiff in most cases is 46 grains of Varget under a 150. Adjust up or down a bit and you'll likely hit the node pretty quick.
There is a higher node with Varget and 150/155s but it involves amounts of powder I hesitate to recommend. The pressure is getting up there and case capacity issues are heavily in play too.
Given the rifle in question I'll bet your application doesn't require every last foot per second. Work the loads to find that lower node.
