Looks like you're going with the Brockton coal?
Good stuff it is.
I had the same issues as you when switching from the 40# bags. Nice thing about the 50#'ers is they exactly fill the coal hod twice.
I just slice the bag above the coal with a knife, maybe a 120 degree arc. Too much and you'll break the bag. Then just hold it from each end and pour. Sometimes it's hard to hold the full bag from the bottom, so just put the bag on top of a milk crate and tip it over. Filling the 2nd hod is really easy.
Something else I tried once and then didn't go back to was putting 4-500# of coal into my landscape trailer and then just shoveling it into the hod. No problems with it, really, it just didn't allow me to use the trailer during heating season.
I think the name of the coal place is Eastern Ice & Coal, but yes, they are in Brockon. They were the cheapest for delivery of a ton (forget the price right now) but I finaly found a place near me where I could buy a few bags to try it out. I burned 2 bags & it was great. My only problem was the flimsy bags it comes in. (the place where a bought a few bags has it stacked up on pallets so they evidently have no problem with the bags, but I did going from bag to hod)
I would be more tempted to build a bin but, in order to keep peace in th house, I would have to make the bin moveable so that I could hide it under our back deck in the summer. My wife could care less what I do out back in the winter, but hates any eye-sores (next to the basement door & visible from our deck) in the summer.