I'm a god-forsaken liberal with <200 hours range time and I tend to agree. On your 3rd or 4th practice you should be able to put 3 in the 3rd ring at 100 yards.

The real mistake was not going for center mass on someone over 70. A gut wound or lung or even a sizeable chunk from meaty tissue anywhere on the body could put down someone that age from blood loss. There's no achievements for head shots in real life.