Speed and trajectory
 

I was out tinkering and increased my draw weight by @2 lbs. (60 to @62). At 60 I was shooting consistent groups out to 40 yards(my limit). After increasing the draw weight, I kept the groups but they dropped @12" from my aiming point. I know the trajectory would be a little flatter but would it be that much or does it depend on the set up? I am shooting a 2002 Cybertec, Versacam 2, 28" Draw, TT rest, Beman ICS 400' s at 27" , with Sweet Spot release. Any knowledge of this would be appreciated. Thanks Chris

RE: Speed and trajectory
 

Are you sure that your sight didn' t move? Possibly your peep slid down a bit?

I have an 03 Razortec and occasionally move around my draw length 60, 62, 65, and have only a very minimal change in my point of impact. 12" sounds like something moved.

RE: Speed and trajectory
 

I have to agree with Redline. Add 2# and you ain' t gonna see squat for change unless you can shoot 60 yards or more. And even at that you' ll only see a couple inches at best. Something else changed.

RE: Speed and trajectory
 

Everything is in the same positions as it was before except the draw weight. I will change the draw back tomorrow and see what happens. Chris

RE: Speed and trajectory
 

This would show a decrease in speed of over 100 fps[:o]

If the site didn' t move, then my guess would be your peep moved a bit or your nocking point moved up.

Something had to change:)

RE: Speed and trajectory
 

Yeah something isn' t right.You may have a tiller problem but even that doesn' t sound right.I agree that something moved.


I changed my draw length down 1/2" and went from 273 fps to 266 fps. The difference showed up @ 60 yards and I was using my 62 yard marking on my sight tape to hit dead on @ 60.There may have been about a 1 yard difference at 50 but I went from 40 yards to 60 without shooting 50.

RE: Speed and trajectory
 

well, i moved my draw weight back to 60 and made sure everything was still in place. I shot 4 arrows just to check my sights at 20 yards. All 4 were within 1" of each other. I thought something had moved to but nothing did. Same measurements as before. Thanks for the thoughts though.Chris

RE: Speed and trajectory
 

RIDGE TRY IT AGAIN IT SOUNDS IF YOU HIT LOW YOU TIGHTEND YOUR TOP LIMB MORE THEN THE BOTTOM WHICH IN TURN MAKES YOUR NOCK GO UP AND THE RESULT WOULD BE LOW SHOTS OF COURSE

RE: Speed and trajectory
 

Fastpassthrough,that is what I was thinking when I stated that the tiller may be off,but 12" is quite a bit.I have never experienced that kind of a change regardless of what I did to a bow.


I also think that he should try it again and see what the result might be.

RE: Speed and trajectory
 

I will increase it again tomorrow evening and let you guys know what happens. It will be tomorrow evening before I can get it done though. I will let you know. Chris

RE: Speed and trajectory
 

I increased it again tonight. I checked the tiller and found it to be out by 1/8" . I adjusted that and checked my peep, cam rotation, peep level and so forth. I shot 4 arrow groups and got them to hit 8" low consistently. After shooting I checked everything again and found it to be right where it was to begin with. I put my draw weight back to 60 and found it to be hitting dead on out to 40(my max). I don' t know why it shoots this way but it does. At 60lbs, my sights are a little higher because of the way I shoot. I don' t know if this would be different if I was shooting in a different form or what. I also don' t know what the trajectory(flatness) of the arrow is at 60 and then at 62+. Maybe one of you techs can shed some light on this. Thanks,Chris

RE: Speed and trajectory
 

Correct me if i' m wrong, but " logically" if you increase your draw weight, you will gain fps, thus flattening the trajectory a small amount. With out moving your sight any, this should cause the arrow to rise a small amount, not drop.

Becuase of my career as an Information Technology professional, I have to ask an obvious question here. And this is not to sound one bit demeaning.....

-Have you tested the draw weight after adjusting it (I' m sure you have) to make sure you were actually increasing the draw weight instead of decreasing it?

I' ve found that myself as well as a lot of my clients tend to miss some of the obvious stuff. Like i said though, i' m not trying to be demeaning or anything of that sort. Just trying to help out. This seems to be a tough one.

Good luck, Hope it works out for ya.

RE: Speed and trajectory
 

What I would quess is when you tighten up your limbs your string also tightens so your peep would be moving...What I mean its not loose but when your moving the limbs(tighter) your string is going to have to move so would your peep plus it would also shorten your draw lenght..Not alot but it will shorten it... Hope this makes sense...;)

RE: Speed and trajectory
 

Ridge,
Is the bow well tuned? An increase in draw weight can get all sorts of funny results if the arrow is not leaving the bow perfectly square. The higher poundage could cause more arrow wobble or oscillation, especially if the arrow is on the lower end of the spine range. This could account for the drop or at least some of it. Just something to check.

Good luck.

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RE: Speed and trajectory
 

Here are the results of what happened to the hitting low. My peep came up @ 3/16"
my rest cord was not pulling my TT up all the way(@ 1/8" short), my draw length was very close to the same. My arrows are just a hair under spine for 62 lbs but I still got good flight. With all of these differences, it came up dropping the arrow @ 8" with a not so precise tuning effort. I got to tinkering after a couple of your all' s questions and just hadn' t put it on here. Thanks for the thoughts and advice. Chris