Specific pec Q

I have pretty good chest development but when i am posing my lower pec around my nipple and working toward inside my arm is a tremendous amount softer than the rest. I feel as though im not even hitting them. My inner, upper and middle areas of my pecs are very sore after workouts but my lower aren't. I usuallly do flat bench, incline flys, and either cable crosses or wide flys. Feedback please what am i not doing?

the wide chest machine by hammer strength gets me a good pump in that area.

im not familiar with that terminology please elaborate. thank you for responding

umm....i don't know how much more i can elaborate....how's this :

hammer strength - brand of gym equipment
wide chest - specific piece of gym equipment made by above

Try some decline bench....works for me.