I have a hammer no mercy death that was drilled at 45...3 3/8ths.....35 that was not hooking much for me.  I have low revs/low track/12.5 degree tilt.  My ball driller said the main reason the ball was not hooking much was the pin to PAP was not good for my style.  He drilled a Track 505C2 for me at 30....4.5....35.  I had not bowled all summer and the ball was hooking nice for me.....I threw 7 good strikes (3 ten pins) a washout, and a sloppy high strike that was a bad throw by me.  Based on what I have been reading I thought a lower pin to PAP meant a stronger backend and he increased my pin to PAP so I was a bit confused by that. 

The No Mercy series of balls used special layouts because the true psa was not marked.  If I remember correctly the recommended strong layout put the HART in the track.  The HART actually marks the intermediate differential instead of the psa.  To locate the true psa and use standard layouts based on its location find the spot that is 90 degrees (or 6 3/4") from both the pin and the HART.  --  JohnP

Ok. Yea I remember that. It was a part of what was going to be the USBC rule where you couldn't have CG further than an inch to avoid needing a weight hole. Hammer was trying to be proactive and create a ball that delivered strong motion with the standard label leverage layout.