In your example this would be about 14% difference in
bullet weight which to me could be significant depending
on what it's being used for (squirrels or rabbits as compared
to say coons or medium sized varmints).
Percentage wise thats about the same as the difference
in the 150 gr vs. 170 gr. bullets, common 30-30 rounds.
There are cartridge energy tables that wouldbe specific.
As is always pointed out though, if you hit game in the
right spot they usuallywon't know the difference.

PKnTX