The spine calc puts me at 38+ for a longbow and 39+ for a r/d at 27" bop. I think that the hardness or softness of the release can make a few pounds difference in spine tolerances. I shot a few 45 with 125 at 27" bop. My wife said that I was drawing a bit longer than normal right and left handed, those were okay, as were the 47 to 50 with 150 up front, as were the 53 to 54 27" bop arrows with 160. The arrows that really stack are 56 to 58 Surewoods 27 bop with 160s and four 5" feathers and three 5.5" feathers, and 1918s with 200 grains up front at 27" bop. When I shoot broadheads I tend to draw until my finger touches the blade, even though that is longer than I normally draw left handed. As soon as my wife points this iPad at me and starts talking to herself while I am shooting, all kinds of odd things happen. But it is deer and turkey time, I need to quit messing with stuff. Last night I tried to call in a little guy just to talk to him and a brother and sister youth hunting teem shot across me and skinned the little guy. The time we went there before, I was ducking to get out of the path of a group squirrel shooters and almost stepped on a wide 8 pointer. Time to get to business and stay away from the busy public lands. That old ragged nontypical is hopefully still around after the beans have been combined, I don't like to hunt when the combines are crowding me.