STS VERTICAL LOCATION

davepjr71 · 03-02-2008, 03:59 PM

I just purchased a chronograph not to long ago and have been recording velocities of my bow with various setups.

Right after I purchased my Vapor Trail Strings I chronographed my arrows at 293 fps consistently and my STS in the location it was all last hunting season. The arrow used is the one in my Sig and weighs 433 grains.

Last week I decided to move my STS as far up the string as possible under the assumption that it would help release the arrow sooner and there bye increase speed. Well, I was really wrong on that assumption.Today I went to the range and at first thought something was wrong with my chrony. However, my buddy shot his bow a few times and the numbers were correct for his bow. My velocity dropped to 280 fps. I also removed my STS and had the same results as the STS up the string 280 fps.

So, I rotated my STS to as far down the string as possible and my velocity went back up to 293 fps. I am picking up 13 fps with the STS!!! I shot about 30 arrows with STS is various locations and without it to make sure what I was seeing is true.

I'm wondering how many of you adjust the vertical location of your STS or do you just put it on as high as possible?

Furthermore, have companies like Bowtech and Hoyt tested the location of the STS when deciding the best location or have they just assumed that is the perfect spot since it is as close to center as possible?

jbowersox · 03-02-2008, 04:39 PM

That is really interesting. I have mine higher up on my string thinking that it would quite the bow more which still may be true. I've tried it both ways and didn't see that much of a difference but I haven't chronoed them either. Very interesting.

davepjr71 · 03-02-2008, 04:53 PM

That was my thought process when I moved mine up. I just didn't expect that much of a difference. Even comparing with and without the STS.

MDBUCKHUNTER · 03-02-2008, 05:22 PM

I think Mathews is onto something by having the string dampeners just above and below the cams!.

gzg38b · 03-03-2008, 06:13 PM

Let me get this straight - STS in the middle of the string was 280.

STS moved down toward the bottom of the string was 293?

Was this the same setup, same day, same chrono?

That's amazing and really suprising to me.

Did you chrono it WITHOUT the STS?

davepjr71 · 03-03-2008, 06:40 PM

yes, same day
yes, same setup, day & chrono
Without STS speed was 280 fps.
Believe me, I thought something was wrong with my chrono. I was getting frustrated big time. Two weeks before I got 293 consistently with the same chrono and the STS half way between highest up and down position. I even asked my friend to shoot my bow I was so confused and he got the same speeds I did. He shot his bow through it a bunch of times and got consistent speeds. So, I knew it was not the chrono.

So, I moved the STS to the bottom and the speed went up to what I had 2 weeks ago. Took the STS off and was back to 280 fps. Moved to top and got 280. Moved to bottom and got 293 again.

gzg38b · 03-03-2008, 06:54 PM

I'm stumped.

Maybe there is a "sweet spot" for string suppressors. I'll have to mess around with mine to see if it makes a difference for me. Interesting.

Holzer · 03-03-2008, 07:45 PM

Makes you wonder how slow the Bear Truth 2 and the Bear Done Deal would be without the 2 suppressors located far from center......? How much speed did the Bear engineers gain? Maybe this has something in common with how/why speedballs work....?

blackfish · 03-03-2008, 08:18 PM

Quote:

ORIGINAL: MDBUCKHUNTER

I think Mathews is onto something by having the string dampeners just above and below the cams!.

I think that can be said for more than there dampeners

nyorange · 03-03-2008, 08:57 PM

Another factor to consider and measure out is how faryour sts is sticking out into the brace height of the string. Does the bow string at rest touch the sts, does it press against the string tightly or even push it out a little. Sounds like it acting like the bridge of aguitar shortening the string and increasing the speed/ vibration of the of the string. Sort of likea temporary shortening of your axle to axle length right before the arrow is released. Just something else to consider. Interesting. take care..