# Why do some bands have draw ratios



## pigeonharvesting (Oct 1, 2020)

Sorry if this question has been posted before, I couldn't find it.
I understand how to work out my draw length, but I've noticed some websites give the draw ratio. I'm interested in some .80 that states "Draw ratio of 6.2 :1 "
Ive been cutting my bands to my draw so I'm around 6.2in / 15cm active and draw 157cm/31in. So I'm dividing it by 5.

Does the ratio above mean divide it by 6.2? So for that band it would be 31÷6.2=5inch active length? Sounds right as it currently feels like it could stretch a bit further, hence to long for my draw.

Sounds right to me, correct me if I'm wrong.
Also seen "Black GZK Slingshot Elastic

Draw Ratio of 1:48. I'm confused now


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## vince4242 (Jan 11, 2016)

I think the point of the website saying what the ratio is is to tell you the maximum stretch ratio. I personally don't stretch past 5 to 1 but some people like to completely max out they're bands. Your stretch ratio is somewhat subjected to how far you want to stretch your bands.


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## Konrad (May 2, 2020)

* "Draw ratio of 6.2 :1 "*

it means 620% 6 point 2 to 1. A elongation value of 620%. You see that is some equations for mixing cement or paint thinning etc. 5.35 to 1, for every 5.35 parts add 1 part of :thumbsup: or 535% watch for the decimal point *(.) *

and colon *:*

Draw Ratio of 1:48 would be 4800% (1:4.8=480%) it is usually 1:5 (500%) or 1:5.5 (550%)

Well the first newbie question I have answered, moving up in the ranks.

Salutations.


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## Trap1 (Apr 12, 2020)

Where (or what sites) do you find these draw/stretch ratios on?


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## High Desert Flipper (Aug 29, 2020)

I have seen the same thing. First, I believe some websites have typo's, as alluded to by Konrad above, like the 1:48 you noted. I have seen this on a website as well and I think this is supposed to be 1:4.8.

Second, I have been paying attention to the stretch ratios as they can vary a lot between different elastics. From what I have seen different brands run anywhere from 4.7 to 6.4. Sometimes the different colors or types within a brand will vary this much- GZK black is listed at 4.8 while vs GZK orange is listed at 6.4 (Wasp slingshots website listings minus assumed typo's). I haven't tried the GZK's yet but am curious. These seem to be real as I have tried several and some are stiff and don't pull very far whereas others are really stretchy and pull much farther. To get good efficient bands one has to hit the sweet spot for loading without breaking.

Maybe most frustrating of all is that some manufacturers don't list the info, or at least not that I can find (I can't find it for Precise elastics). It would be great if they all listed a suggested stretch ratio and a break point. Even better if they graphed loading to see smooth build to stack to max to break. But this would be a lot of data to generate and list, and probably why they don't.

I have tried a few and just found what works well for me and found my two favorites are different, one stretchy and the other stiffer. And this has been part of the fun (experimenting / comparing) as well as part of the frustration. Hopefully all good experience going forward, time will tell.


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## Konrad (May 2, 2020)

Trap1 said:


> Where (or what sites) do you find these draw/stretch ratios on?


Here,

Google slingshotforum maximum elongation.


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## High Desert Flipper (Aug 29, 2020)

Konrad said:


> Trap1 said:
> 
> 
> > Where (or what sites) do you find these draw/stretch ratios on?
> ...


I found some info for tubes and various therabands and a bit of other stuff. I haven't been able to come across this info for some of the newer latex like Precise 3rd gen. But maybe I didn't dig deep enough.

Most of the info I have come across for newer formulations is out of advertising on web sites selling the stuff.


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## Konrad (May 2, 2020)

I agree, High desert flipper, manufacturers web site or here.

Here is a thread discussing precise. https://slingshotforum.com/topic/99458-precise-flat-bands/

I google slingshotforum maximum elongation. PRECISE. You have to dig thru the posts to find it.


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## High Desert Flipper (Aug 29, 2020)

Konrad said:


> I agree, High desert flipper, manufacturers web site or here.
> 
> Here is a thread discussing precise. https://slingshotforum.com/topic/99458-precise-flat-bands/
> 
> I google slingshotforum maximum elongation. PRECISE. You have to dig thru the posts to find it.


Thank you very much for this info! I probably get too hung up on stuff like this instead of just putting it on and pulling it back, but I do love to look through things and ponder the numbers.


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## pigeonharvesting (Oct 1, 2020)

Trap1 said:


> Where (or what sites) do you find these draw/stretch ratios on?


https://www.waspslingshots.co.uk/product-page/white-gzk-slingshot-elastic-2m-rolls

https://celticcattys.com/shop/ols/products/celtic-cattys-new-white-band-series

Some of the other bands have ratio listed.


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## Konrad (May 2, 2020)

Draw ratio of 5.2 :1 Smooth draw. = 520%

Draw ratio of 6.2 :1 Smooth draw. = 620%

Your on your way.

Cheers Konrad.


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## jazz (May 15, 2012)

I am not sure if I understood the question from the title of your thread - but I think that not "some", but ALL bands (and rubes) have draw/stretch ratios.

By experience optimal draw ratio is 5 for all rubbers since they have more or less same chemistry.

less than 5 means less power and lower velocity of your ammo but longer band/tube life. More than five means more power and more velocity of your ammo but shorter band life.

For plinking, someone might choose less than 5, for for hunting it might be 5.5, 6 or even 7.

I do not think there is a magical formula but you have to choose by yourself based on your requirements and conditions.

For example, if you have limited budget and live in the country where everybody charges high shipping cost (like I do) then a sheet of TBG is so precious for you that you will never go for 5 or more..

cheers,

jazz


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