Arrows: Arrow speed / bow # vs arrow weight

How fast will a 44# bow be able to push a 400grain arrow?

Is there a calculator somewhere out there?

Originally Posted by bjarup

How fast will a 44# bow be able to push a 400grain arrow?

Is there a calculator somewhere out there?

will there not be a sh!t load of variables you dont know that could affect the result? ... like the limb efficiency, bracing height, string composition, arrow material, arrow wind resistance and prob a lot more!

You're probably right.

No further questions.

Google 'Stu Millers calculator'.

Originally Posted by bjarup

How fast will a 44# bow be able to push a 400grain arrow?

This might give you a bit of an idea ...

http://www.archery-interchange.net/f...ow-speeds.html

Can you rearrange this "Energy = half x mass x velocity squared" to get an answer "at a constant temperature in a controlled environment etc"?

I've just copied that off the medieval draw weight thread - but I saw Pip Bickerstaffe too and he talked about using this formula to calculate the bow weight based on the arrows found and knowing max poss speed that a wooden bow can project an arrow...so must be able to do the reverse?

Bow performance is complex...
but as a rule of thumb, if you take the total weight of your arrows in grains, and devide it by the weight held by the archer... then two bows of the same model should shoot the same speed if the grains per pound are equal.

For example a 30lbs XXXX brand 68" ILF target bow will shoot a 9gpp arrow (270grain) arrow at the same speed as a 60lbs XXXX brand 68" ILF target bow will shoot a 9gpp arrow (540 grain)

So it allows you to compair bow performance better.

maybe that will help...

Edited to remove text as I just spotted MissChievous's post !

Originally Posted by BorderBows

Bow performance is complex...
but as a rule of thumb, if you take the total weight of your arrows in grains, and devide it by the weight held by the archer... then two bows of the same model should shoot the same speed if the grains per pound are equal.

For example a 30lbs XXXX brand 68" ILF target bow will shoot a 9gpp arrow (270grain) arrow at the same speed as a 60lbs XXXX brand 68" ILF target bow will shoot a 9gpp arrow (540 grain)

So it allows you to compair bow performance better.

maybe that will help...

I shoot with 55# on my fingers, a 400 grain arrow would be 8.1 gr per #, so if my mate with 43# on his fingers is shooting a 348 gr arrow we might hope to see similar performance?

Originally Posted by steve58

I shoot with 55# on my fingers, a 400 grain arrow would be 8.1 gr per #, so if my mate with 43# on his fingers is shooting a 348 gr arrow we might hope to see similar performance?

if your shooting the same make and model of bows... then yes... though release techneque can change things by as much as 4fps...

i wouldnt expect a 8gpp out of a 40 quid set of limbs would come out like 8gpp from a 400 quid set of limbs.