What is the feasibility of using a standard 100' loader and just loading that from the larger reel? Is there any convenient way to do this?
The convenient way is to 3D print a 400ft to 100ft tool. I did this for my first 400ft roll and didn't like the method for the following reasons:
1) Its extra time spent breaking up 400ft to 100ft when a bigger bulk loader solves this
2) It's difficult to accurately split 400ft up into four equal 100ft roils, I have ended up with 5 rolls of different length on my first attempt. This possibly leaves me with 5 short rolls at the tail-end which isn't cost effective to develop with a lab.
3) I love shooting Fuji motion film which are completely a decade expired by now. I didn't want to waste any film as with point 2 and it was much easier to store and organise a 300ft roll cans than three 100ft rolls. It adds up when there are multiple cans.
At the time, $150 for a 400ft bulk loader was logical for me.