# Chrony Test Using Theraband Gold



## hawk2009 (Dec 30, 2009)

Right I have made another video chrony testing thersband gold and I will be making another sometime this week on the tubes.
let me make it clear from the start this is not about Johns gamekeeper catapult it is about my draw length and the speeds I get with my 32 inch draw on my previous video I used the catty with the original band which was to long for my draw so I have cut them down to my maximum draw length as you will see using the original length the scores using 10mm lead wer as follows 170.8 165.7 162.4 170.5 162.0 the two shots taken today with 10mm lead has much improved with scores of 210.0 and 210.3 the reason i made this video is because on a previous thread I asked forum members to say weather they altered the length of the tubes or bands when they purchased a slingshot or used it as it is some did alter them and others did not , so would it not make sense to contact the seller and ask for custom made tubes or flats to be made to your draw length rather than complain that they are to short or to long when you receive them, as I noted some comments made were about chinese tubes being to short when you purchase a slingshot from dankung this has been known for some time thats why I make up my own. having said that back to the video these are the best results I can get and im a little dissapointed as many chrony tests show speeds of up to and over 400ft per sec im' not a power freak but I did expect more so my question would be is it never going to be a possibility because of my short draw length I assume rightly or wrongly it' has alot to do with size, the bigger and longer your draw the better the result. having tested these as close to maximum draw as I can I would say you would get a reasonably decent shot out of them but pulling like that is not my cup of tea, pinpoint accuracy is a definate no no oh well i suppose you cant have the best of both worlds. I will be posting one on the chinese tubes and you can voice your opinion on them but for me I'm still sticking to tubes sorry folks.


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## slingshot_sniper (Feb 20, 2011)

Hawk why have you put a link to sign into ebay?


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## gamekeeper john (Apr 11, 2011)

hawk you need to change the link lol


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## hawk2009 (Dec 30, 2009)

I have not done anything ebay have changed how they display everything im pretty miffed and not able to follow it at the moment i will have a look but dont know if I can do anything about it. right got it and changed it.


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## gamekeeper john (Apr 11, 2011)

heres the link = 




if you did want to get speeds of 400+fps experiment with extreme tapers and smaller pouches, i did this and managed to get up to 548fps, also try tapering your tubes, (fold the elastic halfway back on itself and bind together) also i found that on a warm/hot day i was getting about 30fps faster.


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## gamekeeper john (Apr 11, 2011)

hawk, can you tell me the length of the bands from the top of the fork to the start of the pouch? thanks john


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## hawk2009 (Dec 30, 2009)

gamekeeper john said:


> hawk, can you tell me the length of the bands from the top of the fork to the start of the pouch? thanks john


Yes John the spare has not been touched and is 225mm total length the set I have cut is now 185mm. as you can see from the video they are being pulled right back,i'm not criticising your set up it's very good . what im getting at in this video is if people but custom made slingshots do they alter the length of the tubes or flatband if not and I assume many dont from the comment in the previous thread I put up,as I have not in the past they are not getting the best results also does the size of the person matter after this I think it does what is your draw length John.


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## Brooklyn00003 (Feb 28, 2010)

Do I understand right that your set is from top of fork to pouch is 8.5 cm?



hawk2009 said:


> hawk, can you tell me the length of the bands from the top of the fork to the start of the pouch? thanks john


Yes John the spare has not been touched and is 125mm total length the set I have cut is now 85mm. as you can see from the video they are being pulled right back,i'm not criticising your set up it's very good . what im getting at in this video is if people but custom made slingshots do they alter the length of the tubes or flatband if not and I assume many dont from the comment in the previous thread I put up,as I have not in the past they are not getting the best results also does the size of the person matter after this I think it does what is your draw length John.
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## gamekeeper john (Apr 11, 2011)

Brooklyn00003 said:


> hawk, can you tell me the length of the bands from the top of the fork to the start of the pouch? thanks john


Yes John the spare has not been touched and is 125mm total length the set I have cut is now 85mm. as you can see from the video they are being pulled right back,i'm not criticising your set up it's very good . what im getting at in this video is if people but custom made slingshots do they alter the length of the tubes or flatband if not and I assume many dont from the comment in the previous thread I put up,as I have not in the past they are not getting the best results also does the size of the person matter after this I think it does what is your draw length John.
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i think hes got that wrong because that makes the pouch longer than the elastic lol


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## hawk2009 (Dec 30, 2009)

Yes typed it wrong 185mm sorry. 225 uncut I'm extremely tired on nights again and cant sleep only got three hours today but it's my last night on continentals and I get eight days off before my next shift Yahoo.


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## timdix (Oct 1, 2010)

Very interesting.
it looks like you are using much too much rubber for the those lighter rounds. Remove one of the bands,put on a 5cm length kangaroo leather pouch and shoot butterfly to over 5x the length. You should would get MUCH higher velocity for the 10mm shot with a soft draw. If you got much less than 300fps on a hot day I'd be very suprised. 
25mm of gold theraband with a taper is about the sweet spot for 10mm ammo from my chrony testing. 
I believe John's readings completely. I'm sure he's giving it some real stick which is not everybody's bag. I'm sure his bands are superb for 50cal+ ammo but for lighter stuff....


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## philly (Jun 13, 2010)

Hey Hawrk, thanks for the interesting threads. Like many others here I too have often wondered how band length and cut effects speed and ultimately performance and accuracy. Comparrison to actual draw is whats important, not some artifical speed produced by 50" draw lengts and wierd heated tapers. If someone is after a speed record, thats fine, just report is as such so there is no confusion as to what the goal is.

Stop apologizing Bud, your vids and comments are very informative and I for one find them very useful in my quest to better my performance.
Phily


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## M.J (Nov 1, 2010)

I used a set of John-Boy's Hyperbands which are TB Gold cut 22cm long, tapered 22x9mm, doubled. Granted these are very extreme, but they zipped a 9.5mm stell ball through both sides of a free-hanging empty steel bean can with ease. I'll have some TB Gold equivelent bands soon and will cut them a little less extreme (probably 22x12mm) but I expect them to shoot 250+fps all day long at my regular draw of 34".


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## gamekeeper john (Apr 11, 2011)

very interesting! it seems the longer your draw is the faster you can shoot! but if you choose speed over band life you can get very fast shots with a easy short draw just by using a greater taper! but theres one thing for sure everyone shoots different! like hawks draw isn't has long as mine so he can't get the speeds i do with theraband, but on the other hand theres a lot of pepole out there with a longer draw than me who could get greater speeds, this is a very interesting topic and i bet 50% of pepole who shoot catapults on here are shooting with the wrong band length / taper / lb draw for them, i will do a test soon with varios bands and tapers and measure the draw and lb on camara.... i'm more than sure you can get a draw of 30inch to shoot faster than a draw of 40inch at the same draw weight just be adjusting the taper slightly, so it doesnt mean you can't get a lot of power because you have a short draw its all about how you use your draw correctly, also people with a shorter draw could be much stronger than someone with a long draw and therefore would be producing more lb of draw, as i say everyone shoots different, and in the end it comes down to, draw weight, draw length, tapers, physical strength, weather temperature, ammo, grip on the ammo, pouches, low forks on the catapult for less wrist strain allowing you to get more pull and so on.... i bet joerg could shoot any band set at 300fps lol......... john


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## gamekeeper john (Apr 11, 2011)

timdix said:


> Very interesting.
> it looks like you are using much too much rubber for the those lighter rounds. Remove one of the bands,put on a 5cm length kangaroo leather pouch and shoot butterfly to over 5x the length. You should would get MUCH higher velocity for the 10mm shot with a soft draw. If you got much less than 300fps on a hot day I'd be very suprised.
> 25mm of gold theraband with a taper is about the sweet spot for 10mm ammo from my chrony testing.
> I believe John's readings completely. I'm sure he's giving it some real stick which is not everybody's bag. I'm sure his bands are superb for 50cal+ ammo but for lighter stuff....


yes i agree with you, my bands don't perform very well with light ammo, but they are hunting catapults not target plinkers, i do have a target catapult in the range with single target bands that could shoot a 9.5mm steel at 300fps all day with a light draw, thanks john


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## philly (Jun 13, 2010)

gamekeeper john said:


> very interesting! it seems the longer your draw is the faster you can shoot! but if you choose speed over band life you can get very fast shots with a easy short draw just by using a greater taper! but theres one thing for sure everyone shoots different! like hawks draw isn't has long as mine so he can't get the speeds i do with theraband, but on the other hand theres a lot of pepole out there with a longer draw than me who could get greater speeds, this is a very interesting topic and i bet 50% of pepole who shoot catapults on here are shooting with the wrong band length / taper / lb draw for them, i will do a test soon with varios bands and tapers and measure the draw and lb on camara.... i'm more than sure you can get a draw of 30inch to shoot faster than a draw of 40inch at the same draw weight just be adjusting the taper slightly, so it doesnt mean you can't get a lot of power because you have a short draw its all about how you use your draw correctly, also people with a shorter draw could be much stronger than someone with a long draw and therefore would be producing more lb of draw, as i say everyone shoots different, and in the end it comes down to, draw weight, draw length, tapers, physical strength, weather temperature, ammo, grip on the ammo, pouches, low forks on the catapult for less wrist strain allowing you to get more pull and so on.... i bet joerg could shoot any band set at 300fps lol......... john


Good post John, I look forward to your comments.
Philly


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## slingshot_sniper (Feb 20, 2011)

Generally I'm happy with bands that come prefixed to my slingshots as I only shoot at targets however I can call on my banker...12mm lead through 8" [email protected] 50" draw when and if I need it,stuff gets a good thump with that set up..so it seems


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## M.J (Nov 1, 2010)

gamekeeper john said:


> i bet 50% of pepole who shoot catapults on here are shooting with the wrong band length / taper / lb draw for them, i will do a test soon with varios bands and tapers and measure the draw and lb on camara.... i'm more than sure you can get a draw of 30inch to shoot faster than a draw of 40inch at the same draw weight just be adjusting the taper slightly, so it doesnt mean you can't get a lot of power because you have a short draw its all about how you use your draw correctly, also people with a shorter draw could be much stronger than someone with a long draw and therefore would be producing more lb of draw,


I'm sure you're right and a full test (even a cooperative effort among the forum members) could really help. With a good deal of work I bet a chart could be made showing the ideal taper/ length for various draw lengths and ammo sizes. I would limit the test to TB gold and black, as those seem to be most popular. 
Ideal in this case being highest fps. I would probably limit the test from straight taper down to 2:1 as any more than this and you really begin to sacrafice band longevity.


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## philly (Jun 13, 2010)

M_J said:


> i bet 50% of pepole who shoot catapults on here are shooting with the wrong band length / taper / lb draw for them, i will do a test soon with varios bands and tapers and measure the draw and lb on camara.... i'm more than sure you can get a draw of 30inch to shoot faster than a draw of 40inch at the same draw weight just be adjusting the taper slightly, so it doesnt mean you can't get a lot of power because you have a short draw its all about how you use your draw correctly, also people with a shorter draw could be much stronger than someone with a long draw and therefore would be producing more lb of draw,


I'm sure you're right and a full test (even a cooperative effort among the forum members) could really help. With a good deal of work I bet a chart could be made showing the ideal taper/ length for various draw lengths and ammo sizes. I would limit the test to TB gold and black, as those seem to be most popular. 
Ideal in this case being highest fps. I would probably limit the test from straight taper down to 2:1 as any more than this and you really begin to sacrafice band longevity.
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I would suggest including .030" latex as well, Tex bands are widly used by members. This is a great thread.
Philly


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## smitty (Dec 17, 2009)

I , for one, would really like to have a permanent chart posted where it is easy to find, showing draw length and how long the bands or tubes should be. I don't have a chrony, like most others here and it would be great to be able to set up a slingshot for another forum member to shoot right away. Band width would be nice too, listed as something like easy pull, medium pull and hunting pull.
I use a formula that I found works for me, from fork tie to end of pouch, of dividing my draw length by somewhere between 5 and 4. This varies for me because it seems that different rubber stretches more or less than another. Gum rubber feels like it has a ton of stretch and is very responsive for different uses. T-Gold seems to have a definite threshold you have to find and cross into to get good performance and not cross over for band life. Chinese tubes can really be abused in the stretch factor by really stretching them out to the max and still have good life with them. T-Black stretches out longer than T-Gold, I think, so I factor that in when I rig it all up.
For example : A 19mm width of straight cut T-Gold is good for me to shoot targets, with a length of 19cm, but two strips (same width and length) of it on each side of the fork is too heavy for me to shoot accurately for hunting, so I cut it at 16mm width, two strips per side, for hunting and leave the length at 19cm. This same hunting rig is too heavy for me to shoot targets with, because I get tired and can't hit a barn door.
I use a length of 17.9 cm when I rig with T-Black and 19mm width.
I use a width of 16mm and a length of 16.5 on a straight cut of gum rubber for targets.
Am I doing it like others are doing?


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## philly (Jun 13, 2010)

Right you are Smitty, a chart would be very helpful. On a suggestion by Bill Hays on getting some more speed with my existing band selection I cut them to 6"( 1/5 of my draw length) which maximizes their performance for my draw length of 30" and the change was like night and day. I couldnt believe that 1" shorter made such a difference. Experimenting is fun and part of learning but having a good starting point would sure speed up the learning curve. I am liking this thread more and more. Keep posting guys.








Philly


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## timdix (Oct 1, 2010)

I agree too,the more data the merrier.
My objective with my tests has been to create bands that shoot 300fps with lighter ammo such as 3/8 steel and .38 cal lead and achieve a decent band life.
I started out by pushing the limits like many do I think. I found that once you start shooting into the 300's band life really drops away unacceptably. That seems difficult to overcome so far.
For me speeds of around 280-300fps are a compromise which gives several hundred shots at least. With .38 cal lead it hits very hard and flat out to 20-30metres.
I'm very much into the Torsten style with slight modifcations. 
Band length:about 25cm/10inch. Draw length:butterfly to about 140cm/55inch+. Drawing out to 5.5x length is so important to velocity. 
To get better band life for general use I've been using light tapers eg 5:4 (instead of his 2:1). About and inch width of gold TB (ie using about 28-23mm taper) seems about right. I've used black TB and Tex latex also and must say Tex's stuff is my preferred rubber.
I've been enjoying John's chrony testing immensely,one can learn alot by pushing the limits. Keep it up.


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## hawk2009 (Dec 30, 2009)

Thanks for the comments guys John great post now im being understood all this technical stuff is over my head, with me it's what you see is what you get I may post one on the tubes today but i'm very tired after my night shift and may leave it until tomorrow thanks again all.


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## gamekeeper john (Apr 11, 2011)

i dont think you can get the "perfect taper" on my range i taper my bands from 25mm to 20mm, they put out good power and also have a good life span, but on my own personal catapult i use a taper from 30mm to 15mm which doesnt last as long but has a lot more power, so first of all you have to decide if you want speed or band life? with target shooting speed isn't realy that important so band life would probaly be choosen every time as you can shoot hundreds of shots a day, but with hunting i only shoot about 10 shots all day so even extreme tapers last me a long time, i think if there is a chart made for the "perfect taper" there should be one for hunting and one for target shooting, i think its going to be a impossibe task to find the perfect taper as everyones different, for example you could say the perfect taper is 30mm to 20mm as its good power and good band life, but then how can it be the perfect taper if a band set tapers from 30mm to 15mm and shoots faster but just doesnt last as long, i,m going to start a quick poll just to see if pepole prefere speed or band life, tnanks john


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## hawk2009 (Dec 30, 2009)

long life but must be able to make an impact ( Target shooter )


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