# PFS = over 300fps with single gamekeeper target bands and 9.5mm steel (video)



## gamekeeper john (Apr 11, 2011)

well its long overdue that i made my self a PFS, so heres my first try, and judging by the performance it wont be my last, the video says it all -- gamekeeper john


----------



## notchent (Aug 4, 2011)

If you sell that, I'll buy!


----------



## Charles (Aug 26, 2010)

I'll say it again ... you don't need a big honkin' slingshot to shoot with heavy bands at high velocity.

Great job, John. And the wee beasty you made looks lovely.

Cheers ........... Charles


----------



## marcus sr (Jun 5, 2011)

prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


----------



## marcus sr (Jun 5, 2011)

notchent said:


> If you sell that, I'll buy!


i ll have one too if your selling them


----------



## gamekeeper john (Apr 11, 2011)

marcus sr said:


> prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


i got the speed from a combination of a few things, first was its been a fairly warm day by me which adds about 10fps as to a cold day, also i use a light weight pouch, I use a taper of 25mm to 20mm which think is the best combination for band life and speed, also i was shooting at a slightly longer draw than normal (about 38" - 40") I think all of the above help me get over 300fps with single bands,

If in was using a more extreme taper and shooting at a longer draw 400fps+ is easily possible with 9.5mm steel

thanks -- gamekeeper john


----------



## marcus sr (Jun 5, 2011)

gamekeeper john said:


> prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


i got the speed from a combination of a few things, first was its been a fairly warm day by me which adds about 10fps as to a cold day, also i use a light weight pouch, I use a taper of 25mm to 20mm which think is the best combination for band life and speed, also i was shooting at a slightly longer draw than normal (about 38" - 40") I think all of the above help me get over 300fps with single bands,

If in was using a more extreme taper and shooting at a longer draw 400fps+ is easily possible with 9.5mm steel

thanks -- gamekeeper john








[/quote]
thats impressive,thanks


----------



## gamekeeper john (Apr 11, 2011)

notchent said:


> If you sell that, I'll buy!


i ll have one too if your selling them
[/quote]

sorry guys its not my design to sell even though i would love to







I would need permission of Dgui first, so hopefully Dgui will read this and send me a nice PM (wink wink lol)


----------



## Jacktrevally (Feb 14, 2011)

300+fps, that is fast!

Are you on the whey powder?


----------



## gamekeeper john (Apr 11, 2011)

Jacktrevally said:


> 300+fps, that is fast!
> 
> Are you on the whey powder?


yeah mate whey protein, i'm at the gym 5 nights a week, i need to get stronger so i can break the 600fps barrier with non heated bands lol


----------



## Jacktrevally (Feb 14, 2011)

Go for it...

I use to trained regularly before but has stopped now. Left a hole in my pocket with all the cash I've spent on products from, creatine amino acid and proteins!


----------



## marcus sr (Jun 5, 2011)

gamekeeper john said:


> 300+fps, that is fast!
> 
> Are you on the whey powder?


yeah mate whey protein, i'm at the gym 5 nights a week, i need to get stronger so i can break the 600fps barrier with non heated bands lol
[/quote]
if you wanna get stronger ,drop your programme down to 3 nights a week,incorperate the three main lifts,bench press,deadlift,squats,if you wanna programme mate drop me a pm and ill mail you one,or look at working a 5x5 programme,rest is the key


----------



## gamekeeper john (Apr 11, 2011)

Jacktrevally said:


> Go for it...
> 
> I use to trained regularly before but has stopped now. Left a hole in my pocket with all the cash I've spent on products from, creatine amino acid and proteins!


tell me about it, its not cheap if you do it propaly, just eating healthy is expensive these days


----------



## notchent (Aug 4, 2011)

gamekeeper john said:


> Go for it...
> 
> I use to trained regularly before but has stopped now. Left a hole in my pocket with all the cash I've spent on products from, creatine amino acid and proteins!


tell me about it, its not cheap if you do it propaly, just eating healthy is expensive these days








[/quote]

Nonsense - bunnies have plenty of protein ... and you can use the theraband you're not shooting to work out. Hehe, everyone on the forum here should be buff


----------



## marcus sr (Jun 5, 2011)

gamekeeper john said:


> Go for it...
> 
> I use to trained regularly before but has stopped now. Left a hole in my pocket with all the cash I've spent on products from, creatine amino acid and proteins!


tell me about it, its not cheap if you do it propaly, just eating healthy is expensive these days








[/quote]
cretine creates water retention,protein powder makes u fart,progressive training 3 times a week is the way to get bigger and stronger,if you wanna pull theraband no worries,curl a barbell with a 3 inch bar,improves grip,grows your forearms,old school,is the new school,for reference see dinosaur training,or stronglifts 5x5,less time in the gym +growth and strength


----------



## gamekeeper john (Apr 11, 2011)

marcus sr said:


> Go for it...
> 
> I use to trained regularly before but has stopped now. Left a hole in my pocket with all the cash I've spent on products from, creatine amino acid and proteins!


tell me about it, its not cheap if you do it propaly, just eating healthy is expensive these days








[/quote]
cretine creates water retention,protein powder makes u fart,progressive training 3 times a week is the way to get bigger and stronger,if you wanna pull theraband no worries,curl a barbell with a 3 inch bar,improves grip,grows your forearms,old school,is the new school,for reference see dinosaur training,or stronglifts 5x5,less time in the gym +growth and strength
[/quote]

cheers marcus, i will look into it


----------



## NaturalFork (Jan 21, 2010)

300 FPS is amazing. I love slingshots. Also that is the coolest looking PFS I have ever seen. Nice!


----------



## whipcrackdeadbunny (May 22, 2010)

marcus sr said:


> prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


I hunt with singles all the time; for me, the light pouch/ammo combo, and the length of draw, is what does it.


----------



## marcus sr (Jun 5, 2011)

whipcrackdeadbunny said:


> prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


I hunt with singles all the time; for me, the light pouch/ammo combo, and the length of draw, is what does it.
[/quote]
im beginning to think that way as it goes louis,im out at it tonight so gonna give it a go


----------



## Bill Hays (Aug 9, 2010)

Exactly.
Length of draw beats weight of draw all day (and night).
This is something most people still have a problem understanding... especially is they come from an archery background.

I've been using singles for a long time now... hunting, target shooting etc... I can usually get more speed with .50 caliber steel on down using a single band per side setup, than if I use a double per side... because with the lower draw weight I can pull back further comfortably and that gets more speed than pulling heavy double bands a shorter distance.


----------



## Charles (Aug 26, 2010)

Bill Hays said:


> Exactly.
> Length of draw beats weight of draw all day (and night).
> This is something most people still have a problem understanding... especially is they come from an archery background.
> 
> I've been using singles for a long time now... hunting, target shooting etc... I can usually get more speed with .50 caliber steel on down using a single band per side setup, than if I use a double per side... because with the lower draw weight I can pull back further comfortably and that gets more speed than pulling heavy double bands a shorter distance.


Yep, yep, yep .... Listen to this man!!! He knows. Longer draw means higher velocity.

Heavier pull does not necessarily mean higher velocity, even at the same draw length. Just think about the effect of tapering your bands. Tapered bands at the same draw length will give higher velocity than doubled bands, in general. And the tapered bands will have lighter pull. Heavy pull does not equal higher velocity.

If lighter draw weight means you can have a longer draw length, then you are much further ahead.

Cheers .......... Charles


----------



## gamekeeper john (Apr 11, 2011)

Charles said:


> Exactly.
> Length of draw beats weight of draw all day (and night).
> This is something most people still have a problem understanding... especially is they come from an archery background.
> 
> I've been using singles for a long time now... hunting, target shooting etc... I can usually get more speed with .50 caliber steel on down using a single band per side setup, than if I use a double per side... because with the lower draw weight I can pull back further comfortably and that gets more speed than pulling heavy double bands a shorter distance.


Yep, yep, yep .... Listen to this man!!! He knows. Longer draw means higher velocity.

Heavier pull does not necessarily mean higher velocity, even at the same draw length. Just think about the effect of tapering your bands. Tapered bands at the same draw length will give higher velocity than doubled bands, in general. And the tapered bands will have lighter pull. Heavy pull does not equal higher velocity.

If lighter draw weight means you can have a longer draw length, then you are much further ahead.

Cheers .......... Charles
[/quote]

i totally agree, but i do think for hunting its better to have a double band set with a short draw? john


----------



## Bill Hays (Aug 9, 2010)

Why John?
think about it... the vast majority of shots taken on game are when they're pretty still. So the only benefit would be a microscopic amount of time saved on the draw... other than that what would be the advantage of short heavy draw versus longer lighter draw?


----------



## Bill Hays (Aug 9, 2010)

I'm not talking full on butterfly either... just a few inches longer draw makes a HUGE difference in speed.


----------



## Wingshooter (Dec 24, 2009)

Bill Hays said:


> Exactly.
> Length of draw beats weight of draw all day (and night).
> This is something most people still have a problem understanding... especially is they come from an archery background.
> 
> I've been using singles for a long time now... hunting, target shooting etc... I can usually get more speed with .50 caliber steel on down using a single band per side setup, than if I use a double per side... because with the lower draw weight I can pull back further comfortably and that gets more speed than pulling heavy double bands a shorter distance.


Boy you'v got that right Bill.


----------



## danielh (Jul 28, 2011)

Simply think in terms of speed vs weight vs acceleration time, not poundage, that means nothing for slings.

Slings are a plus and minus game, pouches and ammo take away from speed, tapers and draw length(acceleration time) add to the speed.

But i will venture to say shorter draw is more accurate and butterfly is less so, i believe that archery principle still applies.

I will ask tho, BB's are a different game correct? i dont think we can accelerate them in the same way due to how light they are vs wind resistance?


----------



## gamekeeper john (Apr 11, 2011)

Bill Hays said:


> Why John?
> think about it... the vast majority of shots taken on game are when they're pretty still. So the only benefit would be a microscopic amount of time saved on the draw... other than that what would be the advantage of short heavy draw versus longer lighter draw?


i know its next to nothing the amount of time saved but every little helps lol, for me i am much more acurate with a short draw, another reason is when hunting i'm often in bushes or brambles and i think the longer draw might get a bit in the way, i understand what your saying but for me its a short heavy draw for hunting, i would rather use a more extreme taper than a longer draw to get more speed,

for target shooting / trick shots or speed tests i always use a longer draw,

i supose this long v short draw has the same answer as every other topic on here -- everyones different and have there own prefference,


----------



## Charles (Aug 26, 2010)

I have no direct experience with BBs ... which to my mind is .177 caliber steel. Such a light weight projectile will be much more affected by air resistance than a heavier projectile, even though the BB has a smaller cross section. Think about shooting a big ball of crumpled tin foil. It may start out at high speed, but it will very quickly loose velocity.

But the basic point is still the same ... the longer the draw length, the faster the projectile will be moving when it leaves the pouch. What happens after that depends on the mass and aerodynamic characteristics of the projectile. The only deviation from "longer draw length means higher initial velocity" are cases in which the pouch reaches maximum possible velocity at or before the end of its travels. If I shoot two VERY light weight projectiles, it may be that both will have the same initial velocity even though one weighs more than the other ... because they both get accelerated to the maximum possible with the bands and pouch being used. Similarly, if my band and pouch arrangement reach their maximum possible velocity with a given light projectile at a draw length of 36 inches, then drawing to 38 inches will not propel them any faster. (This is analogous to the fact that falling bodies in the atmosphere reach a "terminal" velocity if falling from high enough ... the effects of wind resistance overcome the effects of gravity. Falling from a higher distance will not result in a higher velocity.) Having said all that, I doubt that the materials we are using are going to reach a maximum velocity in our slingshots.

Cheers ........ Charles


----------



## NightKnight (Dec 16, 2009)

gamekeeper john said:


> i supose this long v short draw has the same answer as every other topic on here -- everyones different and have there own prefference,


That is true when it comes to what you prefer to shoot, and how you aim. However, when discussing speed.... physics are physics. A longer draw will always be faster than a short draw at the same draw weight. Period.

Take a look at ZDP's blog post on this:
http://slingshotforu...els-paper-2006/


----------



## Charles (Aug 26, 2010)

Bill and John ... If velocity were all that is at issue, then short heavy draw vs long light draw would be ... a draw!

But I agree with John that when hunting I prefer a short draw ... not that I am much of a butterfly shooter anyway! But I am more accurate with a shorter draw (to my ear hole or just behind) ... my accuracy drops way off if I go further. I also take the point about shooting in heavy brush. One of my main problems is shooting when crouched, or even when lying down ... I just cannot do a long draw in those circumstances.

In this as in other cases, a lot depends on what you are used to and the circumstances in which you hunt. If I only hunted open fields for rabbits where I could just stroll about, or hunted squirrels that have been treed in open woods by a dog, I might well go for a longer draw. But if I am stalking grouse or quail in heavy cover, or shooting frogs from a little tippy pond boat, I want a shorter draw. To each his/her own, and more power to both of you.

Cheers ...... Charles


----------



## timdix (Oct 1, 2010)

I agree Bill,elongation is the key to velocity.
I recently bought some 1745 tubing. A SINGLE strand per side,ultralight roo leather pouch,25cm long,stretched easily to the max (6.2x) acheived 250fps consistently with little wear!!
I find the less rubber the better when it comes to obtaining projectile speed. 
Even Up to mid sized rounds eg .44 lead,I dont think the average strengthed person needs more than 25mm width TBG equivalent. This can be easily pulled 5.5-6x. That will push 300fps with a slight taper for 3/8 steel and near 250fps using 44 cal lead...no huffing an puffing required! 
Band life as always is the catch.


----------



## gamekeeper john (Apr 11, 2011)

i only shoot lead ammo of 12mm or bigger when hunting (10gram +) would a lighter set up with a longer draw shoot that faster than a short heavy draw? i cant help but thinking that because the longer draw is lighter it is going to have more trouble getting the heavy ball up to speed?
as a example when you let go of the lighter bandset its going to take more time to get up to speed? but when letting go of a heavy pull band set its going to launch it off faster? maybe we need a couple of chrony tests with a long light draw agains a heavy short draw? i think the long draw would come out faster with lighter ammo and the heavy ammo would be faster with the short strong draw,

anyway i'm babbling on now lol, and i know nothing about physics or all this technical stuff lol, i'm just going on what i think from my shooting lol, john


----------



## Jacktrevally (Feb 14, 2011)

There's something I can't understand.

Say you have a piece of 25cm stretched to 125cm (500%)

Take the same size and thickness but at 2x12.5 stretch at 62.5cm (500%) Same force in both cases.

Not only when the travel path is longer it get more air resistance because of more material being exposed and shifted through air.

But Correct ne if I'm wrong, doesn't the shorter bands accelerates faster? Since acceleration is the rate of change of velocity and in the second case travels a shorter distance is a smaller time?

There's something that will be determinant? The hysterisis loop, which I guess in both cases aren't the same?









Can someone explain the physics behind this?


----------



## slingshot_sniper (Feb 20, 2011)

I don't understand any of this all I know is when I draw a single band latex 1" straight cut using 12mm lead ammo set up with a 42" draw, when I release something is going to get damaged that is all I need to know I guess


----------



## gamekeeper john (Apr 11, 2011)

Jacktrevally said:


> There's something I can't understand.
> 
> Say you have a piece of 25cm stretched to 125cm (500%)
> 
> ...


thats ecactly what i think, the shorter stronger draw would accelerate faster,


----------



## slingshot_sniper (Feb 20, 2011)

Hmmm! I know another thing,sleep is going to be at zero velocity thinking of this thread lol I may end up using this method to sleep


----------



## Bill Hays (Aug 9, 2010)

Well, you've got a chronograph and a slingshot rifle... so you can experiment with a lot of different setups.... have fun!


----------



## Jacktrevally (Feb 14, 2011)

John, your thinking is on the right track.

------

Now thinking of it, a longer draw or bandsets can deliver what is expected. My opinion on the matter and I stand corrected.

The optimum draw is what in my opinion will deliver the most efficient shot velocity\ energy.

Too short equally not as good as too long? Think of it, take multiple of 7cm long bands and shoot with it and now take a single band which is 50cm long. Both has their draw back, now which one will shoot faster for the least force or area of rubber is the optimum! i.e There's a length where single layer can deliver as much power as a double band with the same draw force. Now, if that optimum falls within the draw that suits a person then it is more likely these category of people will find this more convinient. Among the advantage, less elastic is used therefore cheaper.

Now double bands, this configuration offers an option for other category of people which have to compensate with a shorter draw to acheive what a longer band can do.

For example, my draw is 32 inches and now give me a single band which have to be drawn 44inches to get the maximum output from them, this is not doing me any favour! However, if I compensate that longer draw with 2 pieces which are shorter drawn, I would definetly compensate for that energy stored in a single elastic drawn longer.

Is it good to say that a double band is a more versatile set up for people with a medium draw?

Now, speaking of the optimum, this not only depends on the length but the shape will have an effect. We should always bear in mind that the hyteresis i.e retraction is also important for the speed. Where the input force as well is important i.e the pull weight is not as such a indicative value for the output velocity.

The temperature of the elastic is not the only factor which can increase the output in an elastic, there are other factors like I said above the shape of the bands. E.g a bands cut straight, tapered, or in a segmental curve will not recover similarly.

There is a lot to read and I've just started to try to understand. Experimentation is the way to go to find out as assumptions are verified through experiment.

That's why I want to buy a chrony, this can answer a lot of doubtful question through experimentation.


----------



## maljo (Nov 27, 2010)

Interesting discussion here. I see two facts and a trade off between them:

- a longer power stroke always transfers more power to the projectile (that's why butterfly / albatross gets higher velocities than face anchor for the same draw weight), &
- a face anchor point gives a more consistent reference for aiming and so gives greater accuracy.

Now my enquiry:
I use a face anchor point because it gives me greater accuracy, with butterfly I'm dangerously inaccurate (I tried it indoors & you can still see the chips in the paintwork).
What I'd like to hear is any suggestion about a useable anchor point that allows me to sight along the line of flight of the projectile and gives me a significant increase in draw length - I currently anchor just under the cheekbone immediately under my right eye but that's a short draw length.


----------



## Charles (Aug 26, 2010)

maljo said:


> Interesting discussion here. I see two facts and a trade off between them:
> 
> - a longer power stroke always transfers more power to the projectile (that's why butterfly / albatross gets higher velocities than face anchor for the same draw weight), &
> - a face anchor point gives a more consistent reference for aiming and so gives greater accuracy.
> ...


I use a sideways hold and give the pouch a half twist (well, really a quarter twist ... 90 degrees). I anchor the big knuckle of my right index finger either in my right ear hole or on the mastoid bone just behind. When I cock my head to the right, I am looking down the bands past the fork at the target. That draw is 3 to 4 inches longer than just below your cheek bone.

Cheers ....... Charles


----------



## Charles (Aug 26, 2010)

O.K. guys ... here are some actual tests. I am drawing together results which I have already posted. All of these shots were made with Alliance 105 rubber bands. The draw length was my own, which is about 34 inches. The band length, fork to pouch tie, was 7 inches. The pouches were the same in all cases. I used pickle fork shooters for all tests. I used 3/8 inch steel for all tests.

A. each band was made from a single piece of Alliance 105

draw weight = 6 pounds, speed = 156 fps

B. each band was made from ONE HALF of an Alliance 105. One rubber band was cut on a diagonal to make the two bands for the test.

draw weight = 3.5 pounds, speed =172 fps

C. each band was made from one Alliance 105, cut on a taper which began 1.5 inches from one end and went to the middle of the opposite end ... so less extreme than B above.

draw weight = 4.5 pounds, speed = 165 fps

D. each band was made from one and a half Alliance 105s. The half was used to double the full band for half its length.

draw weight = 14 pounds, speed = 184 fps

E. each band was made from two full Alliance 105s. In short, each band was fully doubled.

draw weight = 18 pounds, speed = 169 fps

I did NOT do tests at different draw lengths. But I strongly suspect that the relative results would be similar, no matter what the draw length. I also did NOT do the tests with different weights of projectiles. BUT I strongly suspect that the relative results would be similar, no matter what the weight of the projectiles. I did NOT do the tests with Thereaband or other latex bands. BUT I strongly suspect that the relative results would be similar, no matter what the type of material used for the bands. I also strongly suspect that for each setup, you would get a higher velocity with a longer draw.

Note a couple of facts about velocity:

(1) Fully doubling the bands performed only marginally better than having single bands cut at a reasonable taper.

(2) Fully doubling the bands performed marginally WORSE than cutting ONE band on a taper into two pieces. In other words, using 4 Alliance 105s performed marginally worse than using 1 Alliance 105 properly prepared!

(3) Fully doubling the bands performed significantly WORSE than half doubling them.

Now, the draw weight of the fully doubled bands was 18 pounds ... the heaviest of any of the setups that I tested. And yet the fully doubled bands performed only at the middle of the 5 arrangements.

I think that when we have to exert a lot of force pulling back the bands, we psychologically expect that we are going to get higher velocities. BUT the tests contradict that psychological feeling. That psychological feeling is an illusion. You will get just about as much power for hunting purposes, but at a lower draw weight, by a set of properly tapered single bands as by fully doubled square cut bands. You will get significantly more power for hunting purposes, but at a lower draw weight, by a set of half doubled bands as by fully doubled square cut bands.

So, consider the set of cut tapered bands. They will give you almost the same velocity as the fully doubled bands, but at MUCH less the draw weight. Hence, you are probably going to be more accurate with them. If in addition you are able to draw the tapered bands a little further and not lose accuracy, you are going to do even better in terms of speed of projectile.

The down side of cut tapered bands is band life. Still, you would be better off both in terms of draw weight and in terms of velocity, to use half doubled bands than fully doubled bands.

I draw these conclusions based on my tests. By all means, I invite all of you to do your own tests.

Cheers ....... Charles


----------



## dgui (Jan 12, 2010)

John you really make Fine Shooters and Fast. I like that PFS too.


----------



## bullseyeben! (Apr 24, 2011)

Nice pfs John, curios what is catching your shots I looks like a towl or sheet? Just curios if at 300fps them shots go through it? Cheers Ben


----------



## THWACK! (Nov 25, 2010)

gamekeeper john said:


> well its long overdue that i made my self a PFS, so heres my first try, and judging by the performance it wont be my last, the video says it all -- gamekeeper john


Hi, John, 
It would have been great for you to have that PFS with you when someone pulled your shirt off and ran away.
: )

Great vid!


----------



## THWACK! (Nov 25, 2010)

whipcrackdeadbunny said:


> prob really stupid question,how comes thats came out so fast with single bands then? thats more than adequate to take game then isnt it?


I hunt with singles all the time; for me, the light pouch/ammo combo, and the length of draw, is what does it.[/quote]

I prefer to hunt with marrieds, as long as they're married to someone else : )


----------



## THWACK! (Nov 25, 2010)

Charles said:


> O.K. guys ... here are some actual tests. I am drawing together results which I have already posted. All of these shots were made with Alliance 105 rubber bands. The draw length was my own, which is about 34 inches. The band length, fork to pouch tie, was 7 inches. The pouches were the same in all cases. I used pickle fork shooters for all tests. I used 3/8 inch steel for all tests.
> 
> A. each band was made from a single piece of Alliance 105
> 
> ...


Charles,

Was that a thesis for a Doctorate in Slingology?? Wow. "Academic, my friend" he said to Dr. Watson


----------



## Charles (Aug 26, 2010)

THWACK! said:


> O.K. guys ... [CUT]


Charles,

Was that a thesis for a Doctorate in Slingology?? Wow. "Academic, my friend" he said to Dr. Watson
[/quote]

Nahhh ... Just trying to shed some empirical light on the question of which is going to serve you better in a hunting situation: fully doubled bands or a set of tapered bands. In terms of draw weight and velocity, the tapered bands, either cut or half doubled, seem to me to be a clear winner.

Cheers ....... Charles


----------



## marcus sr (Jun 5, 2011)

Charles said:


> O.K. guys ... [CUT]


Charles,

Was that a thesis for a Doctorate in Slingology?? Wow. "Academic, my friend" he said to Dr. Watson
[/quote]

Nahhh ... Just trying to shed some empirical light on the question of which is going to serve you better in a hunting situation: fully doubled bands or a set of tapered bands. In terms of draw weight and velocity, the tapered bands, either cut or half doubled, seem to me to be a clear winner.

Cheers ....... Charles
[/quote]
that was a good read charles,thanks


----------



## THWACK! (Nov 25, 2010)

Charles said:


> O.K. guys ... [CUT]


Charles,

Was that a thesis for a Doctorate in Slingology?? Wow. "Academic, my friend" he said to Dr. Watson
[/quote]

Nahhh ... Just trying to shed some empirical light on the question of which is going to serve you better in a hunting situation: fully doubled bands or a set of tapered bands. In terms of draw weight and velocity, the tapered bands, either cut or half doubled, seem to me to be a clear winner.

Cheers ....... Charles[/quote]

Got it. The Darth Vader approach. Of course. I knew that : )


----------



## Jacktrevally (Feb 14, 2011)

Very interesting read Charles. Thanks for the tests.

Just an idea (not saying that the test you carried out are not o.k)

Since single tapered were the fastest, could you try the same taper but instead of single, having double on each side. Both shot with 3\8 steel and 44cal lead.

This should clears the doubts. I'm guessing that the doubles will perform better on the heavier lead! And should performs equally good in both cases on the lighter ammo, but draw weight is more on the double.

My thinking being, you need a bigger acceleration to get the lead moving. Hence the double might be an advantage.

Gamekeeper John, could you fire a 44 cal with your pickle fork single and compare? As we already know you get over 250fps when you use double per side with 44 cal.

Thanks guys.

Kevin.


----------



## Charles (Aug 26, 2010)

Too late tonight ... I will see how my time goes in the next few days. Have to reassemble a double banded rig.

Cheers ..... Charles


----------



## bullseyeben! (Apr 24, 2011)

I look at it simply: doubled bands = a v8 car with plenty of torque to get a heavy load moving.
Single tapered bands= a rotory or zippy 4cyl car, that can get up to fast speed quite quickly without a heavy load to pull...
So ie I've been using 2 layers of tb blue lately because one layer doesn't have the torque to accelerate the shots, being 9mm and .44 lead fast enough.. Tb gold is more than enough cut single layer because its thicker, and has the torque or pulling power... so I.believe heavier ammo can require thicker, or layers to achieve the acceleration quickly, but the over all speed is limeted to the total draw length.
Hence they both will need similar distances=draw to reach max velocity..., cheers Ben


----------



## -SRS-45- (Jul 7, 2011)

lol I got lost about half way through, think ill stick to the old building term 'if it looks right, it is right'. Basically meaning sometimes the numbers just don't work so you're best to use your eyes and judgement.

I have to admit though I don't understand how people reach such high speeds, if you look at the speed chart I did a while ago I couldn't get near 300fps with semi butterfly tbg 25-20mm. Even with double tbg and full butterfly tbb double I was maxing around 230fps. Unless maybe your cut lengths are shorter, or your releasing quicker... I read somewhere that holding tb stretched too long will affect how fast it retracts.


----------



## timdix (Oct 1, 2010)

-SRS-45- said:


> lol I got lost about half way through, think ill stick to the old building term 'if it looks right, it is right'. Basically meaning sometimes the numbers just don't work so you're best to use your eyes and judgement.
> 
> I have to admit though I don't understand how people reach such high speeds, if you look at the speed chart I did a while ago I couldn't get near 300fps with semi butterfly tbg 25-20mm. Even with double tbg and full butterfly tbb double I was maxing around 230fps. Unless maybe your cut lengths are shorter, or your releasing quicker... I read somewhere that holding tb stretched too long will affect how fast it retracts.


----------



## timdix (Oct 1, 2010)

Acheiving the high speeds is very realistic. With lighter ammo such as 3/8 steel heavy bands are unecessary. It's all about getting those bands working hard,ie stretched to at least 5.5x.Add a long draw(butterfly),fast release,warm day,light pouch and you will be north of 300fps,but don't expect a long band life. I started off with fish hunter bands which are actually quite slow for light ammo in the hands of the average person.Now I know better.
By the way Bullseyeben,you really should get a chrony,jump on ebay now.


----------



## bullseyeben! (Apr 24, 2011)

Good to hear from ya Td, yes mate I've been meaning to...


----------



## slingshot_sniper (Feb 20, 2011)

Its all like banana skins to me one can be more slippery than the other...and I've no idea why

Yes I think I need a speed machine myself


----------



## marcus sr (Jun 5, 2011)

bullseyeben! said:


> I look at it simply: doubled bands = a v8 car with plenty of torque to get a heavy load moving.
> Single tapered bands= a rotory or zippy 4cyl car, that can get up to fast speed quite quickly without a heavy load to pull...
> So ie I've been using 2 layers of tb blue lately because one layer doesn't have the torque to accelerate the shots, being 9mm and .44 lead fast enough.. Tb gold is more than enough cut single layer because its thicker, and has the torque or pulling power... so I.believe heavier ammo can require thicker, or layers to achieve the acceleration quickly, but the over all speed is limeted to the total draw length.
> Hence they both will need similar distances=draw to reach max velocity..., cheers Ben


ive got some blue here,hows the bandlife mate?


----------



## bullseyeben! (Apr 24, 2011)

Bloody fantastic mate, I'm still using the same band on all of the Blackwood ss I made.. no sh*t! It seems not as grippy as gold and may produce less friction? All I know without a chrony is the cuts I have used on all the frames produce speed and excellent life...


----------



## marcus sr (Jun 5, 2011)

bullseyeben! said:


> Bloody fantastic mate, I'm still using the same band on all of the Blackwood ss I made.. no sh*t! It seems not as grippy as gold and may produce less friction? All I know without a chrony is the cuts I have used on all the frames produce speed and excellent life...


sounds good to me,i was considering cutting each width 7mm wider to compensate,or would that not be neccersary? ive never used the stuff on any of mine only my sons ,hes 6 so u can imagine how light it is.


----------



## gamekeeper john (Apr 11, 2011)

i can shoot a 9.5mm steel well over 350fps with doube tbg with a anchor point to my ear, 
but when using 3 strips of theraband gold with a extreme taper (30mm to nothing) and a semi butterfly draw i can get around 550fps with a 8mm steel, 
with a double theraband gold bandset and a taper from 30mm to 15mm with a draw to my ear i can easily launch a 12mm lead over 300fps,
you can see all these videos and chrony tests for yourself by clicking on the link to my youtube in my signature below,

to be honest its quiet easy to achieve 300fps with a 9.5mm steel, it gets a bit more complicated trying to get 400fps or 500fps,
a small light pouch and a hot day is a big help, john


----------



## bullseyeben! (Apr 24, 2011)

marcus sr said:


> Bloody fantastic mate, I'm still using the same band on all of the Blackwood ss I made.. no sh*t! It seems not as grippy as gold and may produce less friction? All I know without a chrony is the cuts I have used on all the frames produce speed and excellent life...


sounds good to me,i was considering cutting each width 7mm wider to compensate,or would that not be neccersary? ive never used the stuff on any of mine only my sons ,hes 6 so u can imagine how light it is.[/quote]
This is 2 layers blue...




Straight cut 8" straight cut on the slack @25mm wide... my draw IS approx 43"


----------



## marcus sr (Jun 5, 2011)

bullseyeben! said:


> Bloody fantastic mate, I'm still using the same band on all of the Blackwood ss I made.. no sh*t! It seems not as grippy as gold and may produce less friction? All I know without a chrony is the cuts I have used on all the frames produce speed and excellent life...


sounds good to me,i was considering cutting each width 7mm wider to compensate,or would that not be neccersary? ive never used the stuff on any of mine only my sons ,hes 6 so u can imagine how light it is.[/quote]
This is 2 layers blue...




Straight cut 8" straight cut on the slack @25mm wide... my draw IS approx 43"
[/quote]
hmmm that looked fast as ****,gonna give some that a whirl,cheers ben


----------



## Ted (May 27, 2011)

Charles said:


> O.K. guys ... here are some actual tests. I am drawing together results which I have already posted. All of these shots were made with Alliance 105 rubber bands. The draw length was my own, which is about 34 inches. The band length, fork to pouch tie, was 7 inches. The pouches were the same in all cases. I used pickle fork shooters for all tests. I used 3/8 inch steel for all tests.
> 
> B. each band was made from ONE HALF of an Alliance 105. One rubber band was cut on a diagonal to make the two bands for the test.
> 
> draw weight = 3.5 pounds, speed =172 fps


Charles, those are great tests - thanks for posting them. In Option B, are you cutting the rubber band into two long, thin triangles before attaching the pouch and fork?


----------



## slingshot_sniper (Feb 20, 2011)

But John you are getting 300+fps with single TBG so not much difference with DTBG

And I recall with single light target bands 260fps is easily achievable BTW from what I hear that is more than enough for small game kills

[edit] it seems to me like lumens of light just because you double the lumens,will not give double the light output


----------



## whipcrackdeadbunny (May 22, 2010)

Well I never, this has become popular ... in my own tests (all observation only, no numbers) the single bands (tapered or otherwise) are more than enough with small ammo and a light pouch, but as the ammo increases in weight, so does the need for more power. Pretty simple, but for me it means I'll be using less elastic and ammo for my time; and for the record, I find straight cut singles seem to last much longer than straight cut doubles ... don't know why, but I presume it's friction. I wish I could do math!


----------



## gamekeeper john (Apr 11, 2011)

slingshot_sniper said:


> But John you are getting 300+fps with single TBG so not much difference with DTBG
> 
> And I recall with single light target bands 260fps is easily achievable BTW from what I hear that is more than enough for small game kills
> 
> [edit] it seems to me like lumens of light just because you double the lumens,will not give double the light output


yeah your right, when using small 9mm steel ammo the single bands are fine, the reason i use double is because my cattys are hunting catapults and most people shoot larger ammo with them, the single bands just dont perform half as good as the double with heavy ammo, and to be honest i dont rate 9.5mm steel as hunting ammo, i.v hit game in the past with 9.5mm steel traveling around 200fps and its either run off or flew away, when i'm hunting i like a 12mm lead traveling at 250fps+ and i know i'm killing what i hit


----------



## slingshot_sniper (Feb 20, 2011)

Well at least you think about what you use before hunting and don't use stuff under powered...respect mate.


----------



## whipcrackdeadbunny (May 22, 2010)

I have very little trouble hunting with the lighter sets, and though stuff may escape sometimes, I find it a very rare occurance nowadays. I chose the lighter sets, because I don't like to bruise and ruin the meat (amoung other things); in the past, I've had a few kills that had to be thrown away, because of such things. But, it's a very personal thing, hunting, so let's not turn this into a debate about it. If you want to talk more, let's open a thread in the right section, or you can always pm me.


----------



## Charles (Aug 26, 2010)

Ted said:


> O.K. guys ... here are some actual tests. I am drawing together results which I have already posted. All of these shots were made with Alliance 105 rubber bands. The draw length was my own, which is about 34 inches. The band length, fork to pouch tie, was 7 inches. The pouches were the same in all cases. I used pickle fork shooters for all tests. I used 3/8 inch steel for all tests.
> 
> B. each band was made from ONE HALF of an Alliance 105. One rubber band was cut on a diagonal to make the two bands for the test.
> 
> draw weight = 3.5 pounds, speed =172 fps


Charles, those are great tests - thanks for posting them. In Option B, are you cutting the rubber band into two long, thin triangles before attaching the pouch and fork?
[/quote]

Yes indeed, that is what I did. It is amazing to me that one can get that kind of performance from just one Alliance 105 properly prepared.

Cheers ... Charles


----------



## Charles (Aug 26, 2010)

Kevin, Ben, and anyone else interested ... I did some more tests with heavier ammo, and got very similar results. I started another thread, as I did not want to hijack this one. After all, this thread started out about achieving very high velocities. The guys who are doing that are awesome.

In any case, I believe the only reliable way to tell if one band set or band arrangement is "better" than another is to do tests on the aspects you desire ... band life, draw weight, projectile velocity, etc. Band life is easy ... just shoot a lot! Draw weight can be measured with a cheap hand-held luggage scale. A chronograph of some sort is the only reliable way to measure velocity ... you can use a Chrony or something similar, or use your PC and something like the Audacity program ... I just do not think personal judgement is a reliable measure of comparative velocity.

Cheers ........... Charles


----------



## Jacktrevally (Feb 14, 2011)

Hi Charles,

Thanks for the tests but I've lost you somehow.

Did you double the tapered bands?

Not criticising your test, there's something I want to understand?

It would be interesting to know if bands singly tapered or doubly tapered had a significant increase in speed with a light and heavier ammo.

Comparing a singly tapered with a straight double doesn't have the elastic in same condition since the tapering does have an effect in itself!

There is a ~20% speed gain with 56cal with doubles! We shall not neglect that as well.

Regards,

Kevin.

p.s I need to get a chrony soon, unfortunately due to custom problems I'm hesitating to make the plunge.


----------



## Charles (Aug 26, 2010)

Jacktrevally said:


> Hi Charles,
> 
> Thanks for the tests but I've lost you somehow.
> 
> ...


I did not get a chance to double the tapered bands ... perhaps tomorrow or the weekend.

Cheers ....... Charles


----------



## ZDP-189 (Mar 14, 2010)

NightKnight said:


> i supose this long v short draw has the same answer as every other topic on here -- everyones different and have there own prefference,


That is true when it comes to what you prefer to shoot, and how you aim. However, when discussing speed.... physics are physics. A longer draw will always be faster than a short draw at the same draw weight. Period.

Take a look at ZDP's blog post on this:
http://slingshotforu...els-paper-2006/
[/quote]

Aaron, thanks for remembering me and my work!

300fps is quite achievable; it's not a problem for most bands. However... and this is uncharacteristically scientific... I don't like the 'sound' of those bands. I have a hunch that the bands are over-powered. That is to say that they should be flinging heavier shot to get more efficient hunting power. The flip side, is they could be made easier to draw. It's not something I'd hang my reputation on, but it comes from shooting lots and lots experimenting with the band curves. Anyway, they seem to be doing the trick, so I'm possibly talking out of my backside.

As for whether bands should be short or long draw, I think shooting in the style each person is most comfortable with is more important than absolute performance. If you can't hit the target, it doesn't matter if the balls are missing at 350fps or barely make it to the backstop. Nevertheless, I think it accepted wisdom that:

Long thin bands stretched to near the elastic limit offer the highest velocity
Long thin bands stretched to a a little less than the elastic limit offer the highest energy efficiency
Shorter bands (drawn to an archer's draw position and with the fork in a gangsta grip) offer the most biomechanical stability
Heavier bands (including tubes) last longer and are only marginally less efficient when shooting heavy projectiles

Again, this doesn't mean other bands and shooting systems are any less valid. For example, Chinese tubes and the Chinese eye draw are less energetically efficient and less stable but once your muscles are conditioned for it, it offers very consistent aiming. Also, R Hussey's heavy bands and intuitive style are in complete violation of all my experimentation, but he could have outshot me any day of the week with both eyes closed.


----------



## Jacktrevally (Feb 14, 2011)

Thanks for your time and effort Charles. Muchly appreciated.


----------



## whipcrackdeadbunny (May 22, 2010)

ZDP-189 said:


> i supose this long v short draw has the same answer as every other topic on here -- everyones different and have there own prefference,


That is true when it comes to what you prefer to shoot, and how you aim. However, when discussing speed.... physics are physics. A longer draw will always be faster than a short draw at the same draw weight. Period.

Take a look at ZDP's blog post on this:
http://slingshotforu...els-paper-2006/
[/quote]

Aaron, thanks for remembering me and my work!

300fps is quite achievable; it's not a problem for most bands. However... and this is uncharacteristically scientific... I don't like the 'sound' of those bands. I have a hunch that the bands are over-powered. That is to say that they should be flinging heavier shot to get more efficient hunting power. The flip side, is they could be made easier to draw. It's not something I'd hang my reputation on, but it comes from shooting lots and lots experimenting with the band curves. Anyway, they seem to be doing the trick, so I'm possibly talking out of my backside.

As for whether bands should be short or long draw, I think shooting in the style each person is most comfortable with is more important than absolute performance. If you can't hit the target, it doesn't matter if the balls are missing at 350fps or barely make it to the backstop. Nevertheless, I think it accepted wisdom that:
Long thin bands stretched to near the elastic limit offer the highest velocity
Long thin bands stretched to a a little less than the elastic limit offer the highest energy efficiency
Shorter bands (drawn to an archer's draw position and with the fork in a gangsta grip) offer the most biomechanical stability
Heavier bands (including tubes) last longer and are only marginally less efficient when shooting heavy projectiles
Again, this doesn't mean other bands and shooting systems are any less valid. For example, Chinese tubes and the Chinese eye draw are less energetically efficient and less stable but once your muscles are conditioned for it, it offers very consistent aiming. Also, R Hussey's heavy bands and intuitive style are in complete violation of all my experimentation, but he could have outshot me any day of the week with both eyes closed.
[/quote]
Just because you're not around as much, doesn't mean we've forgotten you.


----------

