awhile back i saw in a magazine, an article for a poor mans way to figure out arrow speed, something about shooting afew arrows at 20 yards with 20 yrd pin, finding the center of the group, then shoot same amount of arrow 40 yards with 20 yard pin, finding center of group, then measure between the points, but i forgot the rest of the equation. anyone know about this?
thank you in advance

Sorry but I can't say that I've ever heard of this sytem .

nubo

I do a lot of tinkering. In fact, that's about all I do anymore. I've seen the chart, I've used the chart. It does NOT work. According to the arrow drop I had from a particular bow the chart said my bow was shooting about 294fps. All the chrono's said 264fps. I've tried other bows with the same results. 30fps too fast.

I wish. I chased 300fps for over 10 years till I figured it all out. It's a bit rough at 27.5" draw. So what happens? I get a Martin SlayR that does 308 at 53# with an IBO setup. FINALLY!!!!!!!

Just to give further info, You can find the chart over on Edersbow.com

I have never chronographed my bow but I tried this equation and it fell right into the category that my bow at the time was supposed to be shooting with the poundage and arrows and everthing. It is sort of a crued way to do it but I think it is probably within 10fps.