I have been reloading for over 20 years and have had very good luck with compressed loads , for a hunting round I prefer a load compressed no more than 10% but I do use a magnum primer for any compressed load, that do take better to temperature changes . but I have always got a lot of smoke and large groups and a very dirty gun when compressing flake powder like unique. I am using H110 in my 300 AAC Blackout when pushing a 150 gr bullet it is filled to the neck even though the seating depth is lower than the neck so it is compressed but it has been the best preforming load in this rifle I have tryed
I have shot lots of compressed loads from various bolt guns over the years, but not in an AR platform. Thanks for the advice.