Often the 2 3/4 low pressure loads require inserting a 20 fiber card to take up room and add enough bulk for a good crimp. Any 2 3/4" load that will fit in a 2 1/2" shell should be fine. I would try the listed load and see if it fits well in the shorter shell. Hodgdon is one powder make who will respond to enquirers about listed and non loads. They have been very helpful to me in the past. When in doubt I would contact them directly and ask your questions.