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Discussion Starter #1
So here’s a question related to FPS and how much your bolt will drop as it travels...

For example, for years I’ve been used to a compound that is about 270 FPS. With that speed I know I can shoot 0-25 and pretty much hit a bull with one pin. Drops about 5” at 30/32 yards. Etc.

So I’d be curious to hear your findings related to your FPS speed. If your bolt is going 340 FPS for example, are you a bullseye from 0-30? 0-35? If your bolt is 380fps... etc
 

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Here you go with a 30 yard zero.

fullsizeoutput_cb7.jpeg
fullsizeoutput_cb6.jpeg
 

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The faster … the arrow, the flatter the trajectory, the wider the parameters of "Point Blank Range" (PBR) where you can hold center of vitals and still get a kill.

Which is why with the ludicrous amount of energy available in crossbows, it's silly to invest in heavy arrows for more penetration. Better to go with "lighter" faster, flatter shooting arrows. More deer are missed and wounded for lack of PBR than lack of penetration. It takes 25ke to put an arrow through a deer. Most crossbows are putting out 100ke+
 

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Wow awesome chart thanks! Is there a source I can go to that provides that graphic for different zeros and speeds?

Am I correct to assume these amount of drop changes based on bolt weight (even though FPS is the same) (I failed physics lol)? I’m assuming the chart just pics a standard weight for all comparisons?
 

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Wow awesome chart thanks! Is there a source I can go to that provides that graphic for different zeros and speeds?

Am I correct to assume these amount of drop changes based on bolt weight (even though FPS is the same) (I failed physics lol)? I’m assuming the chart just pics a standard weight for all comparisons?
184309
 

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I think as first-order approximation, the drop is linear related to speed.
If I remember my physics education correctly, one can view as two separate, superimposed motions. The forward motion is defined only by the impulse from the xbow, arrow weight, and surface/drag.
The second one is the fall motion, solely defined by gravity (and perhaps a bit drag). The 250fps arrow from a cheap recurve falls with the same speed as the 400+ fps arrow from a Ravin. Only the Ravin arrow got ahead much further in that time, so to say.
 

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Wow awesome chart thanks! Is there a source I can go to that provides that graphic for different zeros and speeds?

Am I correct to assume these amount of drop changes based on bolt weight (even though FPS is the same) (I failed physics lol)? I’m assuming the chart just pics a standard weight for all comparisons?
With the same limb poundage, the bolt weight dictates the FPS, so a heavier bolt will shoot slower.

Theoretically speaking, if shot from a horizontal position, a faster lightweight shaft will hit the ground in the same amount of time after release as a heavier shaft will traveling slower. The only difference will be the faster lighter shaft will have traveled farther than the slower heavier one.
 

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With the same limb poundage, the bolt weight dictates the FPS, so a heavier bolt will shoot slower.

Theoretically speaking, if shot from a horizontal position, a faster lightweight shaft will hit the ground in the same amount of time after release as a heavier shaft will traveling slower. The only difference will be the faster lighter shaft will have traveled farther than the slower heavier one.
But … that's if both bows are shot level to the horizon. In reality, the SLOW bow has to be pointed farther upward on a steeper angle to obtain the same zero. It's in effect "mortaring" onto it's target while the fast bow is frozen roping onto target. So, as I see it, the fast arrow flies flatter and will hit the ground first; assuming the same zero as the slow bow. Of course it will also hit the deer or target first since the slow arrow is traveling a longer distance in it's greater arc. :) ;)
 
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I’m talking about gravity's effect on a weight moving horizontally - I still believe speed doesn’t mean squat, they hit the ground in the same length of time.

There was a demo I saw long ago where somehow they timed how long it took a bullet to hit the ground shot from a horizontal position. Then they timed a bowling ball or something like that being drop from the same height as the bore of the rifle that shot the bullet.

They hit the ground at the same time. Gravity is gravity.
 
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