increasing stater for large batches of baking?

increasing stater for large batches of baking?

Hi, I am wondering if anyone has recommendations for increasing a 100% hydration starter from its maintenance amount of 50 g to 10,000 g. I usually simply feed it every 8-12 doing a double or triple amount feeding until I get to the desired amount. While this works okay I do see that the starter doesn’t quite double as I increase it amounts as I climb towards the mid range of what I need. Is there something I should be doing differently? I only use ancient grains for all of my baking and my starter is currently made from Kamut© (khorasan wheat). 

Thank you in advance!!

Source: Fresh Loaf