My guess is definitely way too little KE down range, especially at 55yards. You are shooting a pretty heavy arrow at quite a low poundage draw weight. I've shot quite a few animals at the 45+ yardage and never had any problems. Actually the only one that didn't pass through was a 140lb hog. I shoot a Razortec at 72lb with a 419gr. arrow. My KE is somewhere in the low 70's. I shot a doe at 52 yards with a Magnus Stinger 4 blade and it passed through completely and stuck in the ground on the other side.

Good luck with your decision.