Avalonia steps into the last bit of unclaimed land as a temporary measure, and makes the same offer to the natives there it did when it last expanded: become part of Avalonia where you can maintain your unique culture and live in prosperity, or decline and eventually become part of some hegemony that will erase you as a people.
An Avalonian graduate of the VTI creates the repeating rifle and sells the design to the Avalonian government. It's a bit of a camel, as bolt action rifles were never a focus of significant research in Avalonia, and it uses pinfire rather than centerfire cartridges, but it's a repeater rifle. The Avalonian government wishes to partner with Arcon and Conservatia to share the design to be more along the lines of the next implementation of the needle gun.
Now that Avalonia has a border with Kyrev, an offer is made to establish embassies in each others' capitols. I can't recall if we have those already, but I'm assuming not.