6 dasher works great in my AT with HRD mag kits. I've run everything from 55gr nosler BT varmint bullets to 105gr hybrids. AX308 is the same action as the AT.
If you're going to try 6 dasher in an AI, make sure you have the small firing pin, otherwise you'll likely have primer issues before reaching "normal" dasher loads.
Here's a video from Bison Tactical using Patriot Valley mag kits...