Archery math?

[Preacher Man]

May not be exactly the kind of formula you are after but, I end up using the pathagorean therum a lot. A squared + B squared = C squared. Use it to calculate actual distance to target from an elevated position. It seems like these days the range finders with angle compensation capabilities are at least somewhat affordable though.

[DaveS903]

Should have known I would get these kind of answers

BTW Dave, your formula is flawed, it either has one too many variables or it is missing some information

I left out 'peanut butter' so I wouldn't give away the secret. Oops...

[Slew]

I just pull it back and turn er loose!! past that I have no idea!!!

[Rat]

KE = Weight x Velocity² / 450800

Momentum = Weight x Velocity / 225400

The constants (450800 and 225400) are conversions from Weight to Mass.

To relate Kinetic Energy to Momentum:

Momentum² x 112700 / weight

FOC = (100 x (A-L/2))/L) where A is the balance point measured from the throat of the nock and L is the total arrow length.

I can dig up more but these I have from memory.

[Bisch]

KE = Weight x Velocity² / 450800

Momentum = Weight x Velocity / 225400

The constants (450800 and 225400) are conversions from Weight to Mass.

To relate Kinetic Energy to Momentum:

Momentum² x 112700 / weight

FOC = (100 x (A-L/2))/L) where A is the balance point measured from the throat of the nock and L is the total arrow length.

I can dig up more but these I have from memory.

I knew you would not let us down!!!

Bisch

[Rat]

Speed formulas and rules of thumb.

To adjust the speed from IBO rating:
IBO Standards:
30" draw +- 3/4"
70 lb draw weight +- 2 lbs
350 gr arrow (5 gr/lb of draw weight)

10 fps for every inch above or below 30" draw length.
1 fps for every 3 gr of arrow weight over or under 350 grains.
1 fps loss for every 3 gr of weight on the string at the center serving.
2 fps for every pound over or under 70 pounds draw weight.

[Rat]

From back in the day...
Don't own a chronograph but you want to know your arrow's speed; try this.

Speed is Distance / Time, S = d/t

So, have your assistant stand exactly half way between you and the target, out of the line of fire though, with a stop watch. Start the watch when the shot is heard and stop it when the arrow hits the target. Do this several times and then take an average of the times.

It is imperative that the assistant be halfway between the shooter and the target, this way the sound from the shot and the target travel the same distance to the assistant's ears.

The rest is simple: Simply divide the distance (in feet) by the seconds and you will have your speed in Feet Per Second.

BTW, the speed of sound is about 1116 FPS.

It's not exact, but it's closer than you think.

[critter69]

I use this one a lot to calculate rack size:

All that and it adds up to 120 5/8 gross.

[Texas Grown]

Meat + Potatoes + gravy = full belly

Best one I know.

[tradtiger]

From back in the day...
Don't own a chronograph but you want to know your arrow's speed; try this.

Speed is Distance / Time, S = d/t

So, have your assistant stand exactly half way between you and the target, out of the line of fire though, with a stop watch. Start the watch when the shot is heard and stop it when the arrow hits the target. Do this several times and then take an average of the times.

It is imperative that the assistant be halfway between the shooter and the target, this way the sound from the shot and the target travel the same distance to the assistant's ears.

The rest is simple: Simply divide the distance (in feet) by the seconds and you will have your speed in Feet Per Second.

BTW, the speed of sound is about 1116 FPS.

It's not exact, but it's closer than you think.

Now THIS is cool!

[AZST_bowhunter]

is this the common core antler sizing formula?

here is your common core..

[Rat]

Here's another math/trajectory related tip...

When shooting in brush we have a tendency second guess if we can shoot through a lane and not hit a limb sticking through that lane. Here's how to tell for sure if you can take the shot.

Let's assume we are shooting at a 40 yard target (deer) and 20 yards away there is a limb crossing our shooting lane. One must wonder if that limb is high enough, or low enough, for our arrow to miss the limb and hit the deer. Creeping thoughts of arrows slamming into the limb cloud our thinking and then we either choose not to shot or make a bad shot because of that ****ed branch!

Back to the shot. Draw, anchor and put your 40 yard pin on the deer, then look at your 20 yard pin; is it on the branch? If so, don't shoot, if not, shoot! This works for any obstruction that you know the distance to; this also works if the pin is ABOVE the obstruction. IOW, your arrow will fly OVER the obstruction on it's way to the 40 yard target.

Try it at home with pool noodle if you don't believe me, it works!

[Rat]

Man, how could I forget these? Draw Length estimators!

Wingspan method 1:
Measure your wingspan from the tip of your longest finger to the tip of your longest finger, don't scrunch your shoulders together.

Take this number and subtract 15 and then divide by 2

Wingspan method 2:
Measure your wingspan from the tip of your longest finger to the tip of your longest finger, don't scrunch your shoulders together.

Take this number and divide by 2.5

Using the Wingspan methods I come up with 28.5" and 28.8" respectively; my actual draw length is 28.75".

Fist to Wall Method:
Make a fist and place it on the wall, stand straight with head up like you are shooting a bow; then measure from the wall (in a straight line, not angled down to the fist) to the corner of the mouth opposite the hand that is on the wall.

These methods are used to find the AMMO draw length. IOW, this is the draw length you will set ON THE BOW! I have found that with most people the wingspan methods get to within 1/4" or better. It is not the perfect solution for the EXACT draw length, but it can be used as a very good starting point.

[super_dave]

here is your common core..