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gravedigger
04-02-2011, 11:08 PM
is there a rule of thume for arrow weight to draw weight.my arrows are rated for 75-95 pounds.and weigh 8.9gpi.but im wondering if there is a general rule for oh lets say a 60 lbs bow should it weigh 300 grains,or a 70 lbs bow should that arrow weigh 400 grains.my bow is at 73 lbs and my arrow weighs 382 grains.should i turn down my bow or get a more hevy arrow for that weight.i just get a little lost on this

martinbowhunter
04-02-2011, 11:40 PM
Yes there is a rule of thumb. minimum of 5 grain's per pound of DW. So a bow with a 60#DW should be shooting a minimum of 300 grains including field point. And a bow with 70# of DW should be shooting a minimum of 350 grain and so on and so forth. So for your bow you need a minimum of 365 grain's. So your fine. I'm shooting 69# and my arrow's weigh in at 432 grains. So anything over the 5 grain per pound of DW is personal preferance...........Got it? Simple right? And personaly, if i were you i would go up in arrow weight (this does not mean you have to change your arrow). But this is just me. I don't like being that close (17 grains) To the 5 grain per pound of DW rule of thumb. Or you could just back the limb bolt's out, say, a 1/2 turn to 3/4 turn each so your around 70#, Or you could just add weight to your field point. Or you could leave your arrow's just the way they are. But it's all up to you. What grain field points are you using?

martinbowhunter
04-03-2011, 04:21 AM
is there a rule of thume for arrow weight to draw weight.my arrows are rated for 75-95 pounds.and weigh 8.3gpi.but im wondering if there is a general rule for oh lets say a 60 lbs bow should it weigh 300 grains,or a 70 lbs bow should that arrow weigh 400 grains.my bow is at 73 lbs and my arrow weighs 382 grains.should i turn down my bow or get a more hevy arrow for that weight.i just get a little lost on this

No! a 60# bow will weigh 60#s and same for a 70# bow ........:p

gravedigger
04-03-2011, 04:36 AM
your funy...lol.i got it ez enought to remember.im taking my bow down to 60 or 65 pounds after i can shoot.i got to take it ez,dont want to re fracture the hand befor hunting comes around:eek:..and i shooot 100 grn points and bh

martinbowhunter
04-03-2011, 12:44 PM
Lol. Yes take it eazy on yourself.

Ehunter
04-03-2011, 12:45 PM
I agree with martin, 5gr. /# draw weight. That's a bare minimum regardless of draw weight. The one thing not many people think of is, the more arrow weight you have, (within reason), the more energy that is transferred to the arrow. That means less energy transferred into the bow. Thus, a quieter, longer lasting bow, and better penetration. Looking back on things over the past few years, I think that was a major factor in alot of the limb problems most companies were having. People shooting right at that 5gpi. rating, trying to get the most out of their bows for speed. Well, one day I figured up what my arrows SHOULD weigh according to all the specs, and guess what, they didn't weight what they should have. They came up about 12 gr. light. Still just over the 5gpi mark, but too light for my liking. I try to shoot something at least 45 gr. over the minimum weight for that draw weight. Good compromise between speed, and silence.

bfisher
04-03-2011, 01:16 PM
5 gr/lb is, IMO, a stupid rule. Stupid, stupid, stupid!!!! Just because a manufacurer declares that 5 gr/lb is a hard and fast rule everybody accepts it as gospel. Hasn't anybnody ever heard of the AMO Minimum Arrow Weight Chart? You really need to look at this and do some scrutinizing. This chart is based on more scientific criteria than just an arbitrary number for all shooters, and if you look it's a safer way to shoot for most.

Compare short and long draws on this chart for a given cam and draw weight. This chart, if you look, suggests an arrow heavier than 5 gr/lb when draw lengths get up around 29 or 30" yet bow manufacturers say 5 gr/lb is OK. Notice that draw lengths for the same setup can use lighter than 5 gr/lb.

This all based on what we know. Energy in equals energy out, inus fristion, hysteresis, and other losses. Meaning? Longer draw stores more energy in the bow than shorter draw. Therefore if all shooters shoot the same 5 gr/lb min. then it's obvious that there is more energy left over from the longer draw guys; energy that goes into the bow.

I could go further with this, but challenge others to study this chart and see for themselves what I'm alluding to. We can discuss it further, but for now I have to go shooting. See ya later.

martinbowhunter
04-03-2011, 01:31 PM
5 gr/lb is, IMO, a stupid rule. Stupid, stupid, stupid!!!! Just because a manufacurer declares that 5 gr/lb is a hard and fast rule everybody accepts it as gospel. Hasn't anybnody ever heard of the AMO Minimum Arrow Weight Chart? You really need to look at this and do some scrutinizing. This chart is based on more scientific criteria than just an arbitrary number for all shooters, and if you look it's a safer way to shoot for most.

Compare short and long draws on this chart for a given cam and draw weight. This chart, if you look, suggests an arrow heavier than 5 gr/lb when draw lengths get up around 29 or 30" yet bow manufacturers say 5 gr/lb is OK. Notice that draw lengths for the same setup can use lighter than 5 gr/lb.

This all based on what we know. Energy in equals energy out, inus fristion, hysteresis, and other losses. Meaning? Longer draw stores more energy in the bow than shorter draw. Therefore if all shooters shoot the same 5 gr/lb min. then it's obvious that there is more energy left over from the longer draw guys; energy that goes into the bow.

I could go further with this, but challenge others to study this chart and see for themselves what I'm alluding to. We can discuss it further, but for now I have to go shooting. See ya later.

Yes bfisher, you are correct. But the op just asked if there was a rule of thumb for this. And according to your martin bow manual that rule of thumb is not to shoot your bow with less than 5gr per pound of DW. So i will continue to do what the manufacturer ask. Also bfisher, if you NOTICED what i recomended to the OP i said " if i were you i would go heavier on your arrows". This is for three reasons bfisher, 1) So the bow is more quiet! 2) so your more on the "safe" side. 3) so longer draw archers don't have so much energy going into the bow during the shot.

bfisher
04-03-2011, 03:36 PM
Yes bfisher, you are correct. But the op just asked if there was a rule of thumb for this. And according to your martin bow manual that rule of thumb is not to shoot your bow with less than 5gr per pound of DW. So i will continue to do what the manufacturer ask. Also bfisher, if you NOTICED what i recomended to the OP i said " if i were you i would go heavier on your arrows". This is for three reasons bfisher, 1) So the bow is more quiet! 2) so your more on the "safe" side. 3) so longer draw archers don't have so much energy going into the bow during the shot.

Your point is well taken. And with all due respect instead of answering the OP's question I went off on a tangent. My Apologies to all for that.

gravedigger
04-03-2011, 03:50 PM
Your point is well taken. And with all due respect instead of answering the OP's question I went off on a tangent. My Apologies to all for that.

no need for an Apologie.it all had to do with my question even if it was not a direct answer.bu i did get what i was looking for.just another not for my mind.but i am turning my bow down to 60 lbs as soon as i can shoot.

martinbowhunter
04-04-2011, 01:03 AM
no need for an Apologie.it all had to do with my question even if it was not a direct answer.bu i did get what i was looking for.just another not for my mind.but i am turning my bow down to 60 lbs as soon as i can shoot.

You better hurry up and heal, or i will come, and shoot your deer for you. Which i would have no problem doing might i add.

martinbowhunter
04-04-2011, 01:10 AM
Your point is well taken. And with all due respect instead of answering the OP's question I went off on a tangent. My Apologies to all for that.

I accept bfisher, just as long as you accept my apologie as well. I was just trying to help the op out, to the best of my ability with what little knowledge i have.

gravedigger
04-04-2011, 07:38 AM
You better hurry up and heal, or i will come, and shoot your deer for you. Which i would have no problem doing might i add.

come on out and get your deer.might be a day hunt for a doe,but opening day there everyware.come get your deer.i will drive.my right hand has a slight fracture down the middel so i dont know how long it will take to heal.i refused treatment so i did not have more money put on my allready spendy med bills.

SonnyThomas
04-04-2011, 11:33 AM
bfisher and AMO. Funny how the AMO (now ATA) can have stats showing proper arrows (which comes out heavier than IBO) and bow manufacturers having warranty of 5 grs per pound of draw weight. Of course Hoyt threw in it's two cents last year with their own ATA version of IBO.

Rockyhud
04-04-2011, 01:42 PM
One more advantage to using a heavier arrow, for hunting at least, is the additional momentum gained that translates into greater penetration potential when the arrow hits the game animal. You're chances of getting deeper penetration or a pass-through is increased with a heavier arrow and more so when you combine that with higher FOC. For anyone who wants to learn more on these topics and his extensive broadhead testing I highly recommend reading the Dr Ed Ashby field test reports. They are available here (http://tradgang.com/noncgi/ultimatebb.php?ubb=forum;f=24) and here (http://www.alaskabowhunting.com/Dr.-Ed-Ashby-W26.aspx). Some very enlightening info he has amassed over his 27 years of study.

bfisher
04-04-2011, 04:20 PM
bfisher and AMO. Funny how the AMO (now ATA) can have stats showing proper arrows (which comes out heavier than IBO) and bow manufacturers having warranty of 5 grs per pound of draw weight. Of course Hoyt threw in it's two cents last year with their own ATA version of IBO.

Apparently you have looked at the AMO chart and saw what I did for those longer draw lengths. This is exactly the point I try to make. If going by their suggested minimum for 30" draw and 70# and speed cam a person should use an arrow weighing 487 grains; way over the IBO minimum of 350. This works out to be almost 40% heavier than IBO and what manufacturers suggest as a minimum. Reversing the math IBO is 28% less than AMO recommendation. I would think, just using some experience and common sense that there would be a lot less busted limbs and bow problems if shooting the heavier arrow.

Now looking at the short draw archer, say 27" and the same 70# the AMO recommends a 388 grain arrow; still heavier than IBO but in the same proportion to the stored energy in the bow as compared to the 30" model.

So where am I going with this? Simply that the AMO found that they consider to be a safe minimum arrow weight for a certain draw length, draw weight and cam style and make recommendatons in proportion to the stored energy in the bow instead of having some RULE that is supposed to fit all shooters. Man talk about leveling the playing field for 3D????? It'd probably make bow manufacturers more happy, too, as they'd be replacing less limbs and other parts due to shooting arrows too light for the energy being produced.

I'm well aware that some of the lighter arrows seen at short draws and low draw weight would not be suitable for hunting. I'm just suggesting that there are other ways of thinking about the issue of minimum arrow weight other than just taking somebody's word for everything. Hey, if we didn't have a free thinking society we might still be using clubs and rocks to hunt with.

SonnyThomas
04-04-2011, 05:52 PM
Yes, bfisher, I saw the AMO charts some years back. And years back I responded to a magazine article about speed bows. The article covered most of the speedster and using 5 grs of arrow weight per pound. Back then, if I remember correctly, some or even most bows fell under AMO warranty claims. Evidently, I must have struck pretty close to home as my response about warranty claims was printed in a later issue. There were no disclaimers of my response.