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Finally able to shoot my crossbow after 7 weeks following shoulder surgery. Using a crank to get em to fly. I started by testing the flight of my new spynal tapp arrows with 200 gr ss inserts and 150 gr field points at 20 yds. At 565 gr these are fairly heavy arrows. The first two went in the same hole. I then switched to the 150 gr cutthroat broadhead. The broadhead shot within a 1/4 inch of the field points hitting slightly to the left ( could be operator error?). At this point my shoulder began barking and it was time to call it quits for the day. I plan on testing this setup at 30 yards to see if I can live with the drop. If not I will cut the inserts to drop 50 grains and try again. From there it will be practice with broadheads only to prepare for the upcoming deer season.
 

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Hi GH... The name of the game is GRAVITY. The drop caused by gravity is a function of time of flight. Gravity is an acceleration NOT a steady rate of drop, so the longer the arrow flies the FASTER it drops. The heavier an arrow, the slower it flys, the longer it is in the air, the faster it drops. I hunt with a 570 gr arrow at 15-25 yards using a HHA Optimizer to compensate for drop at launch velocity of 280 fps. I shoot deer in wide open spaces (backyard herd management), so I don't worry about arc. If you are into math, the calculation for drop in inches is: D, in = 1/2 g x 12 x TOF x TOF.
g (acceleration of gravity)=32.174
TOF (time of flight) in seconds= AVERAGE VELOCITY, fps/ feet to the target.
Remember: Arrow loses about 6 fps for every 10 yards of flight due to drag. For my bow, the average velocity over 30 yards would be (280+262)/2 = 271 fps.
 

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Glad to see that you are recovered enough to be back in the game :)
 

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Do remember those stats Gingerjake? I can't remember my wife's name somedays! Well.....maybe there's a reason for that.
 
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