Just curious why you are only using 175-180 grain subsonic loads? I have some loads for a Remington 700 with 208 and 220 bullets. Try reloaders nest or the 300 whisper forum.
I have a bunch of 180 and 175 pills to play with. I was just looking for a recipe to play with since 220/240 gr pills arent that plentiful right now. Goin in a rem 700 whisper also.
Haven't looked at the ft lbs, but my subsonic 220's are passing completely through green alder trees 16" in diameter. I switched to softpoints, but penetration is still way mega.