Originally posted by rocky
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Arrow Speed vs. Weight
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Originally posted by rocky View PostJust common sense bow math. Creed has an IBO rating of 328. At 50 lbs, that IBO rating is 320. You lose 4 fps IBO per 10 lbs. So, we start at 320, and since you have a 28” DL, we subtract 10 FPS per inch, so we’re now at 300 fps. Peep and loop cost app. 7 FPS, so now, we’re at 293. Every 30 grains of arrow weight cost app. 10 FPS. Your arrow weighs 118 grains over 250, (IBO for a 50 lb bow), so, rounding up, 120 grains costs 40 FPS. We’re now at 253 fps. Of course, that is assuming that your Creed actually hits IBO speed.
Interesting.
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Originally posted by lovemylegacy View PostWhy would you decrease the IBO speed? The calculator doesn't call for that. The calculator I used was very close to what I shot through the chrono.
Interesting.
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Originally posted by lovemylegacy View PostWhy would you decrease the IBO speed? The calculator doesn't call for that. The calculator I used was very close to what I shot through the chrono.
Interesting.
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Originally posted by lovemylegacy View PostWhy would you decrease the IBO speed? The calculator doesn't call for that. The calculator I used was very close to what I shot through the chrono.
Interesting.
No matter the terminology, a 60 lb limb isn't going to be as fast as a 70 lb limb out of the same bow, so you must correct for that.
Even if the calculator doesn't call for that specifically (derated IBO), it should be doing the math; if it isn't the numbers will be wrong.
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Originally posted by lovemylegacy View PostWhy would you decrease the IBO speed? The calculator doesn't call for that. The calculator I used was very close to what I shot through the chrono.
Interesting.
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Originally posted by Rat View PostBecause when you use limbs that are 10 lbs lighter than the IBO standard you have to derate the IBO rating, so you go from an IBO rating of 328 to 320.
No matter the terminology, a 60 lb limb isn't going to be as fast as a 70 lb limb out of the same bow, so you must correct for that.
Even if the calculator doesn't call for that specifically (derated IBO), it should be doing the math; if it isn't the numbers will be wrong.
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Originally posted by rocky View PostI’ve only been selling bows and using manufacturer’s data for 18 years, so I’m no expert. I’ll give you back your 8 FPS. You’re now st 261 FPS. Assuming your bow hits IBO. Not many bows do. Why don’t you go to a reputable archery shop, weigh your bow and arrow, shoot through a good chronograph, and get back to us? I may start grabbing Creeds as fast as they come up for sale if they can do those numbers.
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Originally posted by tradtiger View PostBeen trying to stay out of this thread, but I'm compelled to point out that my 67-lb recurve -- while much slower than any of the compounds discussed above -- worked pretty well to propel a 680-grain arrow (maybe 190 FPS) through the vitals of a 238-lb boar for a 100 yard track.
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Originally posted by rocky View PostI suppose we’ll never know about this bow for sure.
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Originally posted by lovemylegacy View PostWell, other than you actually being there when I shot it, I guess not. I was satisfied with its performance. I have laced several Whitetails with it, one this year that just boggled my mind. Been going to the same shop for a long time. Unless I "miss" entered a input on the Chrono(which is possible), it is accurate.
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