I've put in my set up and it says stiff by .015 (it says it.s .415, and my spine is a .400 spine).

How bad is this? It seems like it's not that bad, if I add half an inch to my arrows it puts it perfect.

I'm not striving for perfection, but how close do you all want your spine to be to the target spine? Stiff by .015 looks good to me, I'd rather be a little stiff than a little weak.

Thanks

Ontarget is far from perfect. I wish he would add a slider in there for slope. In other words, if I take my bow, and shoot an IBO arrow thru it, and then shoot say a 450gr arrow, and chrono both, I will know the slope from the velocity vs. wieght curve. Currently with the perf. factor now, it does not change slope. So If I have my ontarget setup for a 450gr arrow, and I know its perfect for my setup, and I want to know what speed I will get with a lightspeed 360 arrow,its not very accurate. Its would be ok 450gr +/-20gr.

.15" stiff is nothing, and worst case for me, I would buy brass collars to add 20gr or 125gr tips.

I have found that if know the speed of a few given weight arrows you can get the program pretty close. You just need to mess with the IBO or AMO speed and efficiency rating until you get the program to give you the same speeds or pretty close for each arrow. It doesn't need to be perfect, within 5 fps or so is plenty accurate.

.15 spine is nothing, I don't worry until it starts to go off the charts. And like Bigcountry said, this thing is not dead no accurate, but it is much closer than any chart or online calculator is. And once you find an arrow that spines right for you bow you can sync or adjust the program to match it. That way in the future it will even more accurate for that particular set up.

I just re installed windows on my computer last week, I hope I can continue using this program, I have not tried to download it again yet to see. I plan on getting a new computer sometime in the future so I don't know if I want to bother with it until then. If I have to purchase a new copy I don't know if I will bother with it or not.

Paul

I tried it on my CPU with Vista, it wouldn't work (i followed their instructions for it too).

It worked on my PC with some older version of windows.

Thanks for the answers.