Ethan+K

Ethan Kinard Period 8 Science Fair Lit Review Broadheads There is a lot of controversy about broadheads in the archery world. Some swear by fixed blades and others swear by expandable broadheads. I’m one of the people who isn’t sure which is better. Based on my research I think fixed blade broadheads will penetrate a target more than expendables. Fixed blade broadheads are tips that are in a triangular shape and have 3 or 4 blades that stay in a fixed position. Since the blades are in a fixed position and have a point at its tip it loses less kinetic energy upon impact with an object. This should allow the arrow to penetrate the target more. Also, because of the triangular shape the fixed blades should enter the target better at angles. I think the fixed blade broadheads will have the most penetration. Expandable, or mechanical, broadheads are more of a straight shaft that also has 3 to 4 blades, but they expand and open up upon impact with an object. Because the blades open when they come in contact with an object they lose much more kinetic energy. This means that they will have less penetration. Also, because of the straightness of the tip, they will have less penetration at angles. These broadheads are designed to make bigger wholes in an object, not have deeper penetration. I don’t think expandable broadheads will have as much penetration. The two types of broadheads will travel at the same speed with the same kinetic energy, but upon impact the expandable loses a considerable amount more than the fixed blades. A reduction in kinetic energy would cause less penetration into an object. Based on my research and prior knowledge, I think the fixed blade broadheads will have the most penetration. This is the note you wanted me to leave reminding you that my computer at home is not working and because of my topic I was unable to access any websites to get information at school. Thanks!

The websites I used I was unable to access but was able to get a little information on the preview for the webpage on Google. http://www.grimreaperbroadheads.com/ http://www.bowonlyoutdoors.com/broadheads.html

Ethan Kinard 10-13-09 Science Fair Materials & Procedure

Materials 1. compound bow & crossbow 2. identical arrows for the compound bow & crossbow 3. 100 grain fixed blade broadhead 4. 100 grain expandable broadhead 5. foam layer block target 6. Glen Del Buck target 7. tape measure 8. skilled archer 9. laser rangefinder 10. ground marker ( stake) Procedure 1. set up the targets 2. use a laser rangefinder to measure a distance of 20 yards from the target 3. place a ground marker in ground to mark the 20 yard distance 4. put arrow tips in each arrow 5. have the same person use the same bow and shoot each type of broadhead into the both targets 6. measure the amount of the arrow sticking out of the target in the front 7. subtract the amount of arrow sticking out from the total length of the arrow to find the amount of arrow that penetrated the target 8. record my statistics in a data table 9. repeat steps 1-8 now using the crossbow 10. find the total length of the arrows used and the amount of penetration 11. then find the average % of arrow penetration