The first arrow is 302gr with a FOC of 6%

The second arrow is 480gr with a 24% FOC.

Both arrows where spined perfectly for the bow.

I first shot the heavy arrow through the crono at point blank 249fps KE 66 ft/lb

Then the light arrow 299fps KE 59.9 ft/lb

Ok now for the fun.

Heavy arrow

10 yds 245 fps KE 64.1 ft/lb
20 yds 241 fps KE 62.3 ft/lb
30 yds 238 fps KE 60.5ft/lb
40 yds235 fpsKE 58.8 ft/lb
50yds231 fps KE 57.1 ft/lb

After a couple of minor tuningadjustments and resighting in for the light arrow.

10 yds 292 fps KE 57.2 ft/lb
20 yds 285 fps KE 54.6 ft/lb
30 yds 278 fps KE 52.1 ft/lb
40 yds272 fps KE 49.7 ft/lb
50 yds266 fps KE 47.4 ft/lb

So doing the Math the heavy arrow lost 18 fps and 9 ft/lb of Ke and the light arrow lost 33 fps and 12.5 ft/lb of KE from 0 to 50 yds.