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cmwr
05-06-2012, 06:46 PM
My silencer has been drilling dimes for a few weeks now. Tonight while shooting I just happened to notice by chance that my arrow and my stab did not follow a perpendicular line with each other. It was pretty bad. Looking down from the top cam with bow standing on ground and arrow centered on arrow rest, the arrow shaft and stab made a narrow X pattern with each other. I knew this couldn't be right. Logic tells me that if centershot is dead on or close, then the arrow shaft when nocked would follow a perpendicular line with other bow components that are running in a straight line with the riser, in particular a stabilizer that is straight off the front. So regardless of how my bow shot, I had to set it right. So I moved my Apache rest a full number on its graduated slide. I went from 2 1/4 on the scale to 1 1/4 to get the arrow in a straight line with my stab. Then I readjusted my sight until I was again hitting bullseyes. At both settings (before and after) at longer distances the arrows "seemed" to fly straight without fishtailing. I have been led to believe if centershot is off it affects arrow flight. So why was the arrows flying so nice before with the centershot obviously off so bad?

And I have yet to be able to bare shaft tune this bow. no matter how good the arrows fly or how tight my groups are, a bare shaft flies so wildly that it misses the target completely at 20 yards. i got one bare shaft stuck half sideways in a 2x4 wall stud of my garage 10 inches to the left of my target that I can't remove. I moved my centershot back to the 2 1/4 to experiment and the second bare shaft hit 3 inches from the first one. Both these were with a fletched arrow in a bullseye before. My older bow bare shaft tuned nicely at 20 yards.

Someone explain to me just what I am experiencing? I am hitting where I aim. I just don't know what in the heck is going on with this bow.

wscywabbit
05-06-2012, 06:56 PM
Well, from how I understand it, the "center shot" is not normally or technically the "center" of the bow. It is where your arrow rests after the bow has beed "tuned".

The exact center of the riser is generally a good place to start, but the arrow may end up left or right of that point depending on tuning. This is due primarily to "archer's paradox";

Simply put, when you release an arrow, it will actually bend away from the riser before it moves forward. The weaker the spine, the more the bend. It is possible to shoot such a light spined arrow out of a high energy bow that it will break the arrow in half before it ever leaves the front plane of the bow.

After an arrow has left the bow, it will straighten itself out, and the fletchings help to get it back on track. This is called "recovery". In order to compensate for this, the rest will actually sit to the left (right handed bow) or right (left handed bow) of center in order for the arrow to hit center after "recovery".

This is also why shooting a bare shaft helps to determine your spine; an arrow that is too stiff will hit to the left of a fletched arrow and a too limber shaft will hit to the right (assuming right handed archer).

Hope that helps! :cool:

wscywabbit
05-06-2012, 06:58 PM
Oh, and you should never EVER shoot a broadhead on a bare shaft... there's no telling where the arrow may go!

cmwr
05-06-2012, 07:33 PM
I am not worried about the shaft sitting dead center with the center of the bow. I am saying the arrow shaft was at an angle compared to the angle the stab. Looking from the top, the 2 were not in parallel lines with each other. They weren't even close. That make sense?

cmwr
05-06-2012, 08:12 PM
This was what I seen originally.
6448

I corrected it to this. The bow shot well each way once sight was set. I don't get it.
6449

wscywabbit
05-06-2012, 08:28 PM
Since the stabilizer is fixed, and the center shot of the arrow will change in reference to the spine of the arrow and how the bow is tuned, the arrow and the stabilizer have no reference to each other, they're independent of each other and will rarely match.

Now that you've moved your rest over to match your stabilizer, try to do a walk back tune to 40 yards; using only your 20 pin shooting at the same point at 20, 30 and 40 yards. I bet the further you get away from your target the further away from center your arrow will hit.

cmwr
05-06-2012, 09:01 PM
Since the stabilizer is fixed, and the center shot of the arrow will change in reference to the spine of the arrow and how the bow is tuned, the arrow and the stabilizer have no reference to each other, they're independent of each other and will rarely match.

Now that you've moved your rest over to match your stabilizer, try to do a walk back tune to 40 yards; using only your 20 pin shooting at the same point at 20, 30 and 40 yards. I bet the further you get away from your target the further away from center your arrow will hit.

Thats a good idea. But I am not sure I can hold that steady to get an accurate reference. So are you saying that chances are the first pic (original setting) was probably the correct setting? I will admit the bow shot dang sweet. It just looked so crooked tonight when I seen it. Also are you saying that if I was to jump up to a heavier or stiffer arrow, my centershot would change probably more closely to match the second pic since the arrow will not flex as much away from the bow during the shot? It is all making sense to me now.

wscywabbit
05-06-2012, 09:08 PM
Even if you don't have the room or a constant enough form to do a walk back, you could try to paper tune it to get it close enough until you have the time/space/experience to get more advanced with it.

Bottom line though, don't worry about the stabilizer/arrow configuration right now, just have fun shooting it and work on your form, your follow through, and keep learning! :)

cmwr
05-06-2012, 09:16 PM
I bare shaft tuned my older bow with great success. This bow shoots bare shafts helter skelter. Even when set up like it weas before and shooting very accuarte and consistent a bare shaft flies out of the bow sideways and will miss the entire target at 20 yards. Can you tell me why? Is it cause I should be bare shaft testing at 10 yds? I did 20 with my old bow and the shafts were flying relatively straight and hit close to my fletched arrows. This bow is possessed though and I give up on bare shafts. I got one stuck in my garage half sideways from tonight in a wall stud i can't remove. Missed a full size target completely at 20 yards. I am suprised it didn't hit the wall sideways with a slap it was so sideways in flight.

wscywabbit
05-06-2012, 09:27 PM
hmm, maybe you could try to shaft tune it at ten and then step back. What is it you're trying to accomplish? The only time I really bare shaft is when I'm trying a new setup or new arrows to see how they spine out and if I need to play with tip weights or draw weight to make them work...

After that I typically paper tune to get my nock set and then french tune to get my center...

cmwr
05-07-2012, 06:06 AM
I guess I thought there was a few ways to tune a bow. One being paper tune which I have never done. And another being bare shaft tune. I was under the impression that both accomplished the same thing and since I didn't have a paper holding device, it was easier for me to do the bare shaft tune instead. I think I am gonna build a paper device and start doing it that way. Never heard of a french tune. I will look it up.