Ammo question...

Hey, guys. I picked up another box of 100 Federal 115 grain 9mm FMJ at Wally World today for $19.95.

I also picked up a box of 50 American Eagle 147 grain 9mm.

What difference should I expect from these two rounds when I take them to the range with my PX4?
Should the impact point on the target be the same at 7 yards with both of them of will one be lower than the other?
I know nothing about ballistics, so I'm hoping someone can explain the difference.

Thanks.

Generally speaking, given the exact same aiming point and decent shooting technique, the impact point of a heavier bullet will be higher than that of a lighter bullet.
However, this effect also is dependent upon the zero of the pistol, versus the distance from muzzle to target.

Given a 25-yard zero, the impact points of the two bullet weights at seven yards will be very close together.
...If you shoot with good technique, that is.