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guam-bowhunter
March 15th, 2005, 08:32 AM
just got my allegiance about a week ago,setting it up was something else,LOL, well here's my question, I usually use a golden key tru center guage or tool too find center shot,but I don't think it's for all bows because my other bow, a reflex express, the manual say's......inside the riser above the rest hole, measure 3/4" out to center of arrow

well guess what, I rechecked it with the guage and it showed me that the arrow need to go out more, eyeballed it and it really looked off, shot it and it fished tailed violently.

so I just did an initial set up,the way the manual stated and started adjusting from their

I would of thought that, that tool would do it, but I guess not, please don't get me wrong about the tool it worked for the older bows just fine just not the new ones ;maybe???

Jabwa
March 15th, 2005, 09:02 AM
In my opinion, it has more to do with the ATA of the bow. Short ATA bows have more cable guard torque built into them and this changes the centershot at full draw.

SpotShy
March 15th, 2005, 10:03 AM
IMHO, center shot tools are some of the most worthless gadgets ever marketed to the archery public. To begin, every bow set up/arrow combination is going to vary when it comes to achieving the correct center shot. Much also has to do with the type of release you use, the amount of torque you apply to the string, and the amount of side to side nock travel you have, the presence of limb twist, and the amount of tention applied by the cable guide. All of this has to be considered but lets not make rocket science out of it. Given you shoot a modern well made mechanical release aid and you have selected a shaft with adequate spine, start by holding the bow out in front of you and look down the centerline of the riser and split that centerline with the string. Adjust the rest (arrow loaded) until the string splits both the centerline of the riser and the arrow. Then look above and below to see that the string also splits the center line of the limb pockets. Lock it down and get a paper tuner. Shoot the arrow at 12-15 yrds, yes I said 12-15 yds. This insures that the arrow has time to stop paradoxing and straightens out in flight. What you want here is at minimum, less than 1/2 inch tear. Perfect holes are over rated. Not everyone has form that can produce a perfect hole. What you are trying to answer here are two questions, Do I have adequate spine and do I have a good starting point for a good center shot alignment. If you have a bullitt hole or less than 1/2 inch side to side tear, get away from the paper and go to the range to group tune. When group tuning, do it at the maximum range you plan to shoot. I like to do this by shooting a plumb verticle piece of electrical tape. The goal is to keep all the arrows on the line. If you can place them all on a 1/2 inch wide piece of electrical tape at say 40 yds, what else can you do to the center shot? If not move the center shot accordingly until you get the best line you can acheive. Another option would be to plumb bob tune. Either method produces better results than a center shot jig or spending valuable time shooting arrows from 5 feet into a paper jig, a method that was developed for tuning finger shot bows and simply determing if one is "close" to having a correct spine arrow. Hope this helps!

hansel
March 15th, 2005, 10:46 AM
I eye balled my centershot, plus it also was parallel with the stabilizer, and it shoots bullet holes. Guess I got lucky, setting up both of my Hoyt's where easy, and both shoot great.

jonnybow
March 15th, 2005, 10:47 AM
Spotshy, excellent post. That was well thought out and very helpful to the guy asking the question. Welcome to AT and thanks for being able to explain something without overdoing it.

We need more folks like you on here!

Jon

Bow-zo
March 15th, 2005, 02:21 PM
Hey Spotshy, how are ya?
I am with jonnybow..Good post. I agree with all except the lining the string with the center of the limb. I know this is just a starting point but if you look the string is just to the left (for a right hander) of center on the cam. What I do is measure from the front of the sight window to the shaft and again at the rear of the sight window to see if the shaft is parallel to the shelf and riser. Usually it will be about 1/8th inch left of center.
I was especially glad to see you mention the paper tune and finger shooters at the end. I have been trying to get people to see that bare shaft and paper tuning is by and large a waste of time unless you are a finger shooter. It is like you said developed for a finger shooter to find the correct spine shaft. It is fine to shoot a arrow or two just to see where you are and how the shaft is flying but some people spend hours in front of paper just to get very frustrated. Bow hand, cable guard, limb flex & twist cam lean, and a host of other items cause more bad paper tears then the nock and rest ever could. These issues need to be looked at and worked out prior to any paper tuning.
Group tuning is the modern way to go. If you have issues with the rest, spine, nock point ect. you will work them out by group tuning much faster and have more fun. You will work on your form at the same time and get plenty of practice.
The walk back or plumb bob method for center shot is in my opinion the easiest for most people as they can see right away the results and what is needed to correct it. I think to many people do not realize the flex from a under spined arrow is up and down not back and forth if you shoot with a mechanical release. They try to reduce side tearing in paper by changing arrows to more or less spine. Side tears are "usually from vane contact If you shoot a release" which you can test for with powder not paper.

Shooting groups with slightly different nock settings will determine the best nock location.
If archers spent as much time making sure their arrows are all "EXACTLY" alike and checking to be sure the inserts and tips, nocks ect. are as straight as they can make them as they did "tweaking" their bow they would see results much sooner and have plenty of fun doing it.
Frank Pearson once said..Buy the best arrows you can afford, make sure they are perfect and then go out and buy a bow to shoot them. His emphasis was on the arrows. Now Frank knows a bow needs to be tuned but not for hours and days. You eye ball most of it and go out and shoot groups.

I know! I know! Some of you think I am full of it and that is fine you can go out and rip all the paper you want. Guys like me and spotshy have been there done that and know it is not necessary for "most" and can get very frustrating at best. I do not paper tune at all and get very satisfying results and I am very particular. If you do not belive me..ask every Pro you run in to and ask them how much time they spend in front of the paper jig. You will be surprised. I was!
O.K. I will shut up..I just want people to have more fun and get results quicker and without the frustation I had for years. It is taking some time and rightfully so but more and more are seeing paper is a thing of the past.

Dave!

SpotShy
March 15th, 2005, 02:37 PM
Bow-zo,
Thanks for pointing out my error. I had a brain flop. You are correct that most limb pocket center lines would be out of line from the center line of the riser. I shoot Mathews and line the sting up with the portion of the riser where the limb bolt holes are exposed on the back side along with the ceterline of the grip. This keeps my eye on track.

Any way, it is funny how much emphasis folks put on paper. I have seen guys spend hours completely disassembling their rigs trying to achieve a perfect hole. Only to have someone else pick it up shoot it and get a clean one on the first try. Why, because they didn't choke the stuffing out of the thing when they shot it. Like my Pappy always said, "You can't explain common sense, either you have it or you don't. I prefer to spend my time shooting at fur or foam rather than crying over ripped paper, but that's just me.

TANC
March 15th, 2005, 03:32 PM
You know, you two guys make some incredibly valid points here. You can papertune a bow all you want, but all it takes is being a little bit off perpendicular when firing the shot, and the tear will reflect it. It's not a science - it's a ballpark thing, and I'm not sure what it's worth. As you say, the real test is that it shoots tight groups, and it's easiest to check that by running a piece of tape horizontally and vertically across a target and focus on one axis at a time. Once you can hit both axis consistently, how much better can it get. When you have achieved that, heck, the paper tune may not even look good anymore, but who cares.

Great post and answers !!

Bow-zo
March 15th, 2005, 04:13 PM
Hi Tanc,
You got it man, If you have clean arrow fight you will shoot tight groups.
And if you are shooting tight groups you probably have clean arrow flight.
The problems alot of archers have is they unfortunatly can not shoot tight groups even with a perfectly tuned bow so they stand in front of paper all day?????
Modern bows and arrows do not need those old outdated tuning methods.
Sure shoot one or two and see if the rip is 6" or 1/2" and that is it.
This all applies only if you shoot a release aid. If you are a finger shooter paper can be a huge help as is bare shaft testing.
When paper tuning first got started Terry Ragsdale after winning Vegas shot his arrows thru paper and got a 6" tear??
Most these guys will go out after days of paper tuning and change everything again anyway when they start shooting groups..Go figure!

Have fun..Dave!

Techy
March 15th, 2005, 04:20 PM
I have always eyeballed it to begin with (never used the tools) then paper and or group tune.

Dave Nowlin
March 15th, 2005, 05:48 PM
The first thing with the Allegiance is look at the cam. On a right hand bow the right track is simply a takeup drum. It has no mechanical advantage. The center track is for the bus cable and the left track is for the string. Now let's think this through, we certainly don't want to be exactly even with the center of the limb as the string is left of center. Eyeball the cam and fiure out how much the string track is left of center then set center shot that far left of center and walk back tune. It's as simple as that. :smile:
Dave Nowlin

opa
March 15th, 2005, 05:52 PM
Centering the string won't work with some bows ( string tracks might not be dead center) and lining up with your stab is not always right ( beiters are easy to bend).

Just strap an arrow against the inside of the riser with a rubber band,
put an arrow on the string and the rest and it's easy to see if they're running parallel. If they do you're dead center.

Opa

guam-bowhunter
March 15th, 2005, 08:55 PM
thanks guys I think I have a better understanding of this topic of bow tuning, so I guess true center shot may not be your center shot, you might have to tweak it left or right to align with your form so your arrows fly true and straight. By the way the allegiance SMOKES!!!......

you guys are just such wonderful help thanks......... :wink: :)