Top_Heavy's World

OK, if you aren't anal then stop reading right here, this is going to be dry and boring for the story lover, but packed full of details and specifics if you are into that!

I have been working with Dave Reisner's 2008 model X Force compound bow. Dave is smaller than I am so keep in mind this is on a 27" draw bow! The X Force is a dual cam, split limb bow. The draw is fairly smooth, but that is partially due to the size and low poundage... that will move it up in the search for the best 60# bow. There isn't any literature with the bow so I don't know what the range of draw poundage is, so I consulted my arrow charts and made sure the arrows Dave was shooting would handle the max. The good part about shooting 27" draw is that you can shoot light arrows upto 70#, so I cranked down the limbs and got a baseline. Dave had it sighted in at 62.6#, that is what he is seen shooting on the Drury vidoes.

The bow would only go to 68# maximum and it made some funny noises to get there. I shot the bow 5 times to get a good, reproducable speed and I lowered the poundage 1 pound and checked again. I did this routine down to and including 62#. I was/am intrigued by the uneven power curve on this bow.
68# draw created 296 fps
67# draw created 293 fps
66# draw created 293 fps
65# draw created 290 fps
64# draw created 289 fps
63# draw created 286 fps
62# draw created 283 fps
These speeds are with a Radial X Weave STL Hunter 200 arrow of 27 3/16" weighing 332.8 grains with a 100 grain head included. This is a dip crested arrow with 3 2" blazer vanes.

I noticed that there were some flat spots in the draw. 64# and 65# had only 1 fps increase and again at 66# to 67#, there was no increase, obviously that is a point of ZERO return for the harder draw. I shot upto 7 times to verify these minimal amounts, and even went back to the scale, they were as real and reproducable as possible. This bow is set up exactly as I would set it up, a drop away rest, a multiple pin sight, a thin handle and nothing but a peep in the string. The brands might not be the ones I would choose, but Dave proves they are very deadly.

The object is to keep the poundage low for ease of shooting and draw, even when cold, but to get the most in energy transfer. At 65# there is a dip and to get to the next increase would take 2 pounds of draw for only 4 fps of increase, where as there is a 3 fps increase per 1# of draw up to that point. Running the numbers on the Kinetic Energy Calculator on the Bowhunting Info site, we see that 62# gives us 59.2 lbs KE while 64# gives us 61.74 lbs KE, an increase of 2.5 lbs KE. We drop to only 1.7 lbs KE increase at the 66# mark, a total of 63.46 lbs KE.

64# with this rig is the point of diminishing returns, and I will bet that is where Dave will be shooting it this season!

This bow specific, super detailed information is good information for finding the sweet spot of your favorite hunting rig. It took over an hour of shooting and tweaking, and I don't know of any proshop that does this, but you can easily do this your self with a few pcs of hardware. With some time you might find that you would get better results from a lower poundage on your bow.
I will soon be doing a piece about the magic number of draw weight to arrow length and how it might be costing you performance, sometimes less is more.