technical question re:KE

[borealboy]

I'm new to trad archery and have a question about kinetic energy. If two different bows have the same poundage rating and the same brace height, do they also produce the same kinetic energy? In other words, are all 50# recurves the same re: killing power. The reason I ask is that if one bow design produces more energy, then I could presumably get away with a lower poundage and get the same results? Compound bow makers always quote all sorts of stats but trad bowmakers just seem to say things like "smooth shooting" which doesnt mean much to me.

[vermonster13]

Not all 50# bows are equal.

[Artur]

A modern, "working" recurve -- the tips straighten out as the bow is drawn -- will usually impart more KE (and faster arrow flight) than a "static" recurve -- the recurved area does not change profile as the bow is drawn (look at a Mongol bow sometime) -- because the "working"  recurve is able to store more actual energy than the "static" recurve. Even when both bows are rated at the same draw weight. A lot of it depends on what the arrow is made of, how heavy that arrow is, bow design/material, string design/material, etc. Or so I have been told...

A recurve, in case you didn't already know, is able to store more energy in its limbs than a flatbow because of the recurving of the limbs. This is also why a 50# longbow has to be so much longer than a 50# recurve. The "smooth shooting" thing refers to how much "hand shock" (sort of like recoil in a gun), if any, a bow has. Some bows with massive KE have little hand shock...

[Pete W]

Bows of the same weight are not the same.
 Look over the reviews of 50# bows on my trad review pages at  www.peteward.com  and you will see the performance from similar bows.

Put the arrow where it belongs and speed is not a  concern.
 You are right about being able to drop bow weight with a higher performing bow.

Pete

[DarkeGreen]

For traditional equipment the easiest way to think about it is how fast the bow shoots the same weight arrow. Yes there are some differences but in general all wood bows are setting on the slow end, then laminated bows, then wood and fiberglass combos, and the the fastest are going to be those using carbon.

There is a person on this site involved with carbon bow designs that would give you exactly what you are asking for. His carbon designs will let you shoot a 45lbs bow that is equal to 70 to 90 lbs bows from other manufactures given the same weight arrow.

With that said any 45lbs to 50lbs modern bow is going to get the job done and you are correct to limit youself to a bow you can shoot often and shoot well.