I would call badger and ask them. I have several bat actions most of them have 1.062 threads. I use a 1.25 barrel with these. My bigger action uses 1.125 threads and they need a bigger barrel. If weight is not an issue the more shoulder on the barrel the better.
Just picked the action up a couple hours ago. This is nothing new to you guys, but let me tell ya, this action is a work of art. This is my second custom action and I am just blown away by it. It is a tank!