Working up the arrow on GT's website it comes up to 420 grains. That's figuring a 28" shaft, 2" Blazers, acculite nock. Plugging the numbers into Backcountry calculator and using 317 fps for IBO speed, 20 grains on the string it calculates a speed of 281 fps with 74 lbs.ft of energy.
This would probably be the maximum speed your bow will achieve if it's tuned very finely. Real world? I'd subtract some more and estimate that it's more like about 270 fps.
A lot of people over estimate things. I've had a lot of people say my arrows are zipping along at 300 fps when in reality they were only dong around 250 to 260. So much for eyeballs.
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