Compound bow - set up question

[GMMAT]

I'm trying to figure something out in my head.

When we set our nocking point up......we do so with a square or a laser level (or some people simply do it by sight.....which is just fine).

So.....Scenario is a 20yd shot.

Now......we talked the other day about the arrow going above the line, when it leaves the bow.....and Matt/PA mentioned it did this at about 8yds (I think)......then re-intersecting the line at the 20yd mark.

WHAT makes the arrow go above the line? I know the archer's paradox on traditional gear is to clear the riser. Why does an arrow shot from a compound react the way it does (going above the line)?

[rybohunter]

It"™s not that the arrows pointed up as it sits on the bow (nock & rest) your bow is pointed up. At least that is the way I envision it. If you drew an ATA line, it would not be perpendicular to the ground. Now all this is minute and might not even be detected just looking at it.

[HuntingBry]

ORIGINAL: GMMAT

I'm trying to figure something out in my head.

When we set our nocking point up......we do so with a square or a laser level (or some people simply do it by sight.....which is just fine).

So.....Scenario is a 20yd shot.

Now......we talked the other day about the arrow going above the line, when it leaves the bow.....and Matt/PA mentioned it did this at about 8yds (I think)......then re-intersecting the line at the 20yd mark.

WHAT makes the arrow go above the line? I know the archer's paradox on traditional gear is to clear the riser. Why does an arrow shot from a compound react the way it does (going above the line)?

Umm, gravity? Seriously, even with the speed of today's compounds we need to compensate for arrow drop so you have to aim slightly upward so the arrow will drop into where you are aiming.

Bowtech may be taking the ARCH out of archery, but it's not gone.

[BobCo19-65]

Notice the arrow path. It will cross the line of sight initially close, then will once again cross further out due to trajectory. There really isn't a trad/compound line in the dirt drawn on this concept.

I probably got the question wrong though.

[GMMAT]

That's what I'm getting at Bry. And Rybo may have eluded to "why". Are we shooting "up" towards the target.......even though our arrow IS "level" (in relation to our bow)? If we drew lines from our peep.....through our 20yd pin......to the target.....that would be a straight line.

The line from our nocking point.......to the "spot" at 20yds would be another straight line.

Would the line still be straight if we added a third point (on the nocking point line) to include the arrow tip?

[rybohunter]

Jeff, I believe the arrow tip would be above the nock-target line.

[Badger_Girl93]

ORIGINAL: GMMAT

Would the line still be straight if we added a third point (on the nocking point line) to include the arrow tip?

No,

The arrow tip is above the nock-to-spot line as rybo said.

Gravity is the reason the arrow must travel up and break the sight line before falling back down into the"spot". If it did not first travel up (in an arc path) there is no way it would ever be able to hit the spot we aim at...

...I think

[Rob/PA Bowyer]

ORIGINAL: BobCo19-65



Notice the arrow path. It will cross the line of sight initially close, then will once again cross further out due to trajectory. There really isn't a trad/compound line in the dirt drawn on this concept.

I probably got the question wrong though.

There it is.

The arrow is shot up to compensate for gravity. If you shot with your arrow perfectly level to ground, your arrow immediately begins to drop thusly, we shoot up so our arrow archs and intersects our intended target. Think about it, the farther we need to shoot, the higher we RAISE our bow.

Same goes for bullets out of a gun. People think the bullet rises out of the barrel but this is not the case. When a bullet leaves the barrel, gravity pulls on it and it immediately begins to drop. The reason people think it rises because the barrel is actually pointed up in contrast to the scope/line of sight to again, compensate for the drop thusly a bullet also has an arch.

[HuntingBry]

ORIGINAL: GMMAT

That's what I'm getting at Bry. And Rybo may have eluded to "why". Are we shooting "up" towards the target.......even though our arrow IS "level" (in relation to our bow)? If we drew lines from our peep.....through our 20yd pin......to the target.....that would be a straight line.

The line from our nocking point.......to the "spot" at 20yds would be another straight line.

Would the line still be straight if we added a third point (on the nocking point line) to include the arrow tip?

No, it couldn't be. Take a look at the very rudimentary illustration below.



All points are going to the same point on the target, but since the tip of the arrow and the nock are not on the same plane because the arrow is notcompletely perpendicular to the ground they cannot be on the same line.

[bawanajim]

If you drew a perpendicular line from the center line of an imaginary circle directly to a theoretical sharp corner would the difference be greater than or equal to the foc of a binary equation?


This is one of those questions I just can seem to find a logical answer to.Any help would be much appreciated.
If it make a difference to your answer. You are on the down wind side of a white oak tree seventeen and one half feet from the ground in a summit viper using non mechanical broad headsthis is on aThursday evening after a Monday new moon hunting public land.