Draw length affecting IBO speed...

Greg / MO · 10-29-2005, 07:23 PM

How much should losing one inch of draw length affect your speed? Say, if something shot 318 fps (IBO) at 30", how much would you lose by going to a 29" draw length?

I remember seeing this before, but can't remember... thought it was like 5-6 fps.

Matt / PA · 10-29-2005, 07:38 PM

Depends alot upon the efficiency of the cam system and the actual draw length (some cams lose more speed in the lower draw length range than others because of the design platform being around a 30" bow).......but the basic rule of thumb is approx 10fps +/-for every inch of draw length gained or lost.

Greg / MO · 10-29-2005, 08:17 PM

Thanks, Matt.

What got me wandering was there's a new Bowtech dealer in our neck of the woods, and I was looking at a Patriot SC he had on the wall. The birth certificate said 311 on it with a 29" draw, and I know the advertised range is 318-326. If you added 10 fps to that, it would be in the ballpark.