If you're shooting a modern bow at 60lbs plus, penetration won't be a problem. As long as you're using a quality broadhead, which some were mentioned by Antler Eater. We've used many broadheads over the years to take elk from two blade solid construction to three blade fixed both in 100grn & 125grn, never have shot four blades but am sure they'll do the job. As far as shoulder blades go I would'nt recommend that shot with any head to much can go wrong. If an elk is somewhat broadside you would want to aim for the crease just behind front shoulder about 10inches up from his belly so a shot near the shoulder blade should'nt come into play. If you miss the crease and hit above front leg you'll still get plenty of penetration and still be well under shoulder blade and it's a deadly shot. In the area we hunt there's quite a few camps with about 30 total hunters off and on, I know most use either thunderheads or muzzy's in both 100 or 125grn, our camp all use muzzy 125grn and have no intention of changing. We shoot ics beman 400's and are confident out to 40yds. Like I say if it ain't broke don't fix it. hope this helps. elknut1.

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