I have some victory made guide gear arrows from sportsmansguide. They are 350 spine with 200gr insert from ethics and 125 broadheads.....580gr if I remember correctly.....they tune good but that is about the max tip weight before they get squirrelly....29 arrow, 28 draw, 55 draw weight. 350 spine is the stiffest they offer in that guide gear which is made by victory. I harvested a doe last season and had a pass through with scapula contact and a heavy quarter away....entered well behind the last rib, contacted the shoulder, and redirected out the neck.....like 24inches of the arrow fully inside the body, bone strike, and still able to pass all the way through.