Grandviewer

gzg38B Hey thanks that's great software. Real tells you all about your setup, bow, arrow shaft selections and point weights. Again thanks for mentioning it.

Paul L Mohr

That is the software that I have and will run your numbers on. You can download a free trial if you like (I think they still do that), and then if you like you can upgrade it for 25 bucks I think. That is what I did.

That is the exact information I needed, thank you for posting it. I will play around either tonight or tomorrow and see what I come with for you. I should have something for you by saturday at the latest, maybe tonight if I can get to it.

There is nothing wrong with shooting longer arrows than are required. As long as you get the spine correct. Other than they will weigh more than they need to, which is what you are going for anyway. Many target shooters shoot longer arrows with heavy point weights so they can have a bigger diameter arrow. They need the longer length and heavier tip to break down the spine. Weight and speed really isn't an issue when shooting at known distances.

That is the nice thing about these programs, as long as you know your draw length you tell the program any arrow length and it will tell you if it will work. Online calculators and charts base your draw length off from the arrow length you use. This would require you to shoot the proper length arrow. Which is one inch past where the arrow contacts your rest. And your rest should be set up so the contact point on the arrow is right above your grip (most forgiving spot). So your correct arrow length is usually 3/4 of inch less than your draw length. Many shoot arrows that are the same length as thier draw length. This usually isn't a problem unless you are REALLY close on being weak on spine.

Same goes for you switching from 100 to 125 grn heads. The difference is pretty mininal and usually will not effect most set ups. Normally if you see a difference it is from the design or profile difference in the blades, not the weight.

However since you switched from one type of arrow to another and are interested in shooting more arrow weight we might as well see what works for your bow and what is available.

Are you looking for anything specific? Like a certain speed you don't want to go under ( I can't garuantee that, I don't know how accurate my program will calculate that for sure), or a certain weight you are looking for, or a certain type of arrow you want to shoot.

My honest opinion is if you want to shoot carbons of moderate weight see if you can get Arrow Dynamic Nitro Stingers. I will let you know what size. I tend to prefere aluminum arrows, but these are the best carbon arrow I have shot with fixed blades period! They are a tapered design which makes them flex different and gives them better FOC. I don't know that I would want them for a target arrow, but they are really nice for a hunting arrow. Thier only downfall in my opinion is they have weak nocks.

By the way the cybertec is one of my favorite hoyt bows. I came VERY close to getting one with a versa cam a few years ago. I was actually going to get one when I got my new bow, but they discontinued them.

Paul

Paul L Mohr

Oh, you can check the draw length of your bow by drawing it with an arrow nocked (pointed in a safe direction and your finger off the trigger!). Then have someone mark your arrow where the hole is that your rest mounts to. Let the bow down and measure from the string ( with your arrow still nocked, push it back on if you have to) to the front of the insert of your arrow (not the tip). Then add 1 3/4 inches to that measurement. That is the AMO draw length of your set up. That doesn't mean it's the correct draw length for you, just what the bow is set to.

Paul

MonsterBuckDreams

That brings up this question: I'm guessing that when an arrow is rated for a certain draw weight range, i.e. 55-65 (which is what mine is)that rating is for that arrow uncut as it comes from the factory right? This would mean that since I got 2 inches cut off the arrow, it would increase or strengthen the spine which favors or is more accomodating toa heavier BH?

Speed's really not an issue as long going from my current 366gr to 391gr is not going to slow my arrow down to some ridiculous number like under 200. Considering I'm probably just gonna slap on 125 BH'sinstead of a 100's (putting me at 391gr total) the speed for that weight should be 228 fps. I'd like to see how close I am to your program.

No need because silly me, instead of coming here to ask you guys firstI'd already bought somearrows 2 weeks ago. The arrows I will be using unless your program tells me there's something tragically wrong it them are the CX Terminator Lite Select 4560'sfletched with 4 inch feathers and tipped with a 125gr BH.

Why?

The Cybertec has a brace height of 63/4 inch which makes it very unforgiving by industry standard right?

And speaking of forgivenesswhydoes "setting up your rest so the contact point on the arrow is right above the gripmake forthemost forgiving spot"? Mine is btw, but just curious.

Paul L Mohr

Lots of questions and I don't have time to answer all of them now.

I ran your bow real quick yesterday and the arrows you have show that they spine well with 125 grn tips and 28 inches. That is all the farther I got though. The Maxima's were good as well, and to be honest probably better arrows, just lighter. If anything both arrows are a tadd stiff, which is not always bad, too weak is bad.

I think spine on arrows is measured at either 28 or 29 inches, I don't remember which. Not full length though. And the program takes that into account anyway. You need roughly a .400 spine if I remember correctly.

I forget what the aluminums were, I think 2117's? I will play with it more later. Today is my day off, but I have lots to do. (should be doing it now)

I just liked the way the cybertech shot and felt in my hands is all. 6 3/4 is not that short of a brace height either, 7 is considered good. Really depends on your form.

I will get back to you later.

Paul

Paul L Mohr

Ok after making some adjustments I show the Terminator lights with a 125 grn broad head and 4 inch feathers being slightly stiff for your set up. Like I said, not a bad thing really. You could probably increase your draw weight to 65 lbs or so and have them spine well. Which is nice considering you are at the bottom of the weight range.

I was getting messed up by the fact that these are Terminator LIGHTS, not regular terminator selects. These are not in my data base. No big deal though the spine deflection is the same for either, it was just throwing my weight off is all.

As far as your difference going from 100 to 125 in speed, it won't be much and probably not as much as you think. I get closer to 233 fps instead of 238 ish. Let me know what happens when you shoot them over a chrono that way. Heck you should have slapped one on and checked it while you were there. What I can tell you is you will notice no difference in performance. The speed difference either way is not enough to effect trajectory or KE or your sight settings.

With the 125 grn head and 4 inch feathers you should have around 15% FOC which is really good for a hunting arrow. They should fly pretty darn good for you if they tune well.

If you have trouble tuning them I would look at these things. First check for contact issues with your rest or harness. Probably not a huge deal with feathers, but it is normally the first place you look. Then I would take a close look at the arrows. Spine test them to make sure they are all straight and the inserts are square to the shaft. Fixed blades need to spine very true in order to fly right. While you are doing this check the nocks as well, many don't look at the nocks, but have bad nock fit is just as bad as bad inserts.

Number your arrows and watch what they do. If you have one or two flyers all the time see if they are the same arrows. If so don't use them to hunt with, save them shooting with field points up close or ditch them.

After this if you still can't get the arrows to tune and you are confident the nock setting is good and centershot is good look at your draw weight. Try turning it up a little at a time and see if things get better.

This is providing you shoot well to begin with. Inconsitant form and grip will make it very hard to tune. What you may think is a tuning issue could be you changin the way you grip the bow from shot to shot. Or you are anchoring in a slightly different place each time. Anchor will usually show up as up and down misses, and grip will usually show up as side to side misses. Both combined will really mess you up.

Just remember don't expect to tune any better than you can shoot to begin with. And if you are not a pretty good archer expect your fixed blades to shoot slightly larger groups than your field points do. They are not as forgiving to shoot.

If you want to gain some speed the first thing I would do is change peep sights and put on a string loop. Taking all that weight off your string will help alot. It will also move get your arrows closer to the correct spine. Get a peep that does not use a rubber tube, those things suck up speed and make noise. The string loop will help align your peep for you. I like the round cheereo looking peeps myself. Or a timber line NO Peep is a good option as well.

Paul

Paul L Mohr

Ok, I will try to explain why having the rest in the correct position is more forgiving. Basically it boils down to a simple lever. When you grip a bow you will torque it. I know of no one that can draw a bow and induce no torque to the grip. This will pivot the risor to the side, and in turn move the prongs of your rest. Since your arrow is connected to the string in the back and rests on the prongs of the rest it will pivot with the rest moving the point of the arrow from side to side.

Having the contact point of the arrow to the rest directly above your grip, or where the rotation is originating from will induce the least amount of movement in the arrow. If your rest is set up behind your grip (an overdraw) it will work as a lever and magnify the amount of movement at the tip of your arrow. So any inconsistancies in your grip will be magnified from shot to shot. This is why Overdraw rests are looked at as being less forgiving and should only be used by experienced archers.

An easy demonstration of this would be to lay an arrow on a table. Hold the arrow in place towards the front of the arrow. Move the back of the arrow from side to side one inch letting the arrow pivot where you are holding it. Now hold the arrow towards the back or in the middle and move the back from side to side one inch again. The tip of the arrow moves much more now than it did before.

This isn't exactly how an overdraw works, but it shows the effects pretty well.

Most drop aways are overdraw rests, but not much, maybe an inch or two and can be shot pretty well. Now the old overdraw rests used by 3-d shooters that were 4 or 5 inches back could be pretty tricky to shoot. And there is really no need any more with the faster bows and lighter arrows to choose from. Bascically an overdraw let you shoot a shorter arrow, which reduced weight. And since the arrow was shorter and stiffer you could get away with a lighter spine as well, which ususally means less weight too. Now a days if you want a lighter arrow, just pick a lighter arrow. You don't have to sacrifice forgiveness for speed.

I actually shoot a longer arrow than I need for the opposite reason. I have this thing for 2213 aluminum arrows (don't ask why?). So to get them to spine well with my set up I need to shoot them a little long. This also increases my weight which is ok with me too. Of course if I wanted more weight I could shoot a different size alunimum with a thicker wall.

Good luck, I hope I helped some and didn't confuse you too much.

Remember these are only opinions and nothing more. I don't claim to be a expert or anything.

Paul

MonsterBuckDreams

So this would mean that if I didn't switch to 125gr BH's, I'd really be out of the spine range right? Specifically, the arrow with a 100gr BH would be way too stiff at 60lbs?

The proshop saidmy arrows were for a weight range of 55-65. Does your program have info to cross reference this?Reason I ask is 'cause according to the proshop, I should be right in the middle of the spine range but your program shows that I'm at the bottom and need to increase draw weight in order to spine well. I'm a little confused.

As for everything else that you wrote Paul, I will re-read. Looks like great info. Again, thanks for the individualized attention. It's guys like you that make this place great.

-Heu

TFOX

These programs go into SPECIFICS,chartscover a wide range.Some charts ask for hard or soft cam but a program uses the actuall speed that a bow produces and uses that efficiency rating to find a proper spine arrow.


Example,I have a friend that has the charts call out a 400 spine for him but he is using a very aggressive cam.My program shows heneeds to use the arrow at 65#'s but the chart says he is okat 70#'s(If memory serves).He had lots of trouble grouping at 70#'s and I tried to explain why but he didn't get it.SO,I TURNED HIS POUNDAGE DOWN and he started grouping.It was all in the spine.

Paul L Mohr

There is very little difference between 100 and 125 heads dynamically. It might be an issue if you were weak on spine and switched to a 125 head. However if you were right on or a tad stiff I doubt it would effect anything. It would effect your FOC some, but you have plenty of that as well.

I do not believe your arrows would be "Way too stiff" with the 100 grain heads. If you have both I would try them both and see if it shoots better with one over the other.

Remember this is all estimation, even with a fancy program. Nothing is going to give you exactly what you need or garuantee that it will work. They will just get you close, and the programs are more accurate than the charts because they ask for more data. I had to turn my bow up 5 lbs to get the arrows I am using to bare shaft tune perfect. This is just a starting point, not a diffinitive answer. And carbon arrows use the same arrow to cover a larger span of uses, so you are going to end up with a stiff arrow depending on how your set up is, unless you alter arrow length or increase draw weight.

I need to look some stuff up and switch computers and I will give you some info on arrows and how spine works.

Paul