# Comparing Double 1745 To Single 1745 (video)



## Wingshooter

I have been using these single 1745 for a short while and I am constantly amazed at what they do. I set up a set of doubles the same length as the singles I have been using. I checked the amout of pull using my garage scales not real accurate but they showed the doubles pulling about twenty pounds at 32 inches. The singles showed 10 pounds at 32 that is just what Ray said in his post.
The doubles are harsh for me to pull. At 75 I no longer pull the heavy bands with ease. I hate to admit it but alas it is true. So I set up my crono and you can see the results. I am using 1/2 inch steel foor this test. I will let all you young bucks pull the heavy stuff I am sticking to the easy way. Like Bill says if you want more speed just pull a little farther.


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## treefork

No point in doubling up on those!


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## Henry the Hermit

Wingshooter said:


> I have been using these single 1745 for a short while and I am constantly amazed at what they do. I set up a set of doubles the same length as the singles I have been using. I checked the amout of pull using my garage scales not real accurate but they showed the doubles pulling about twenty pounds at 32 inches. The singles showed 10 pounds at 32 that is just what Ray said in his post.
> The doubles are harsh for me to pull. At 75 I no longer pull the heavy bands with ease. I hate to admit it but alas it is true. So I set up my crono and you can see the results. I am using 1/2 inch steel foor this test. I will let all you young bucks pull the heavy stuff I am sticking to the easy way. Like Bill says if you want more speed just pull a little farther.


I get similar results. There is certainly more power in doubled bands, but not more speed, unless you reach the point of overloading the bands. 1/2 steel is obviously not an overload for the singles set. If my tests are a guide, with 1/2 inch lead or heavier, the doubled set will outperform the single.

Like you, I'm leaving the heavy pull bands to the younger guys.


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## newconvert

thanks for the vid Roger, first question? how young is young bucks?







i have been leaning towards tube shooters also, very impressive, and much cheaper to shoot!


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## Wingshooter

Henry in Panama said:


> I have been using these single 1745 for a short while and I am constantly amazed at what they do. I set up a set of doubles the same length as the singles I have been using. I checked the amout of pull using my garage scales not real accurate but they showed the doubles pulling about twenty pounds at 32 inches. The singles showed 10 pounds at 32 that is just what Ray said in his post.
> The doubles are harsh for me to pull. At 75 I no longer pull the heavy bands with ease. I hate to admit it but alas it is true. So I set up my crono and you can see the results. I am using 1/2 inch steel foor this test. I will let all you young bucks pull the heavy stuff I am sticking to the easy way. Like Bill says if you want more speed just pull a little farther.


I get similar results. There is certainly more power in doubled bands, but not more speed, unless you reach the point of overloading the bands. 1/2 steel is obviously not an overload for the singles set. If my tests are a guide, with 1/2 inch lead or heavier, the doubled set will outperform the single.

Like you, I'm leaving the heavy pull bands to the younger guys.
[/quote]
I think the 1/2 inch steel at 115.7 grain is about the limit on the singles. I shot a hex nut that weighed in at 159 and the speed was so slow the ft pds was the same as the 1/2 inch steel One thing I forgot to mention this has to be the quietest slingshot I have ever shot.


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## Wingshooter

newconvert said:


> thanks for the vid Roger, first question? how young is young bucks?
> 
> 
> 
> 
> 
> 
> 
> i have been leaning towards tube shooters also, very impressive, and much cheaper to shoot!


I think anybody under 70 would qualify.


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## M.J

I finally got single 1842s to put 7/16" steel balls through a steel can at 10m. They're just over 5" long for my 30-31" draw, just about bottomed out. Still very light and smooth.
Good stuff, Roger!


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## lightgeoduck

I like how singles shoot, but shooting doubles makes it easier for me to line up my shot for some reason...

Thanks for sharing.. videos like these keep me out of the dog house at home... my wife doesn't want me to buy more stuff, and how do I explain a chrony?









LGD


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## Dayhiker

Boy, that just baffles me. One tube is out performing two tubes with the same load? Yet clearly there is more power in the doubles? How is that in evidence in this particular experiment? Apparently it isn't. Very strange.

Of course when even heavier ammo like the hex nut mentioned is used, the extra "power" comes into play. This just doesn't seem logical to my very small brain. The answer is probably best explained in the mathematics of the thing, which till now I haven't taken the time to ponder. I suppose Dan or Joerg or somebody has explained it somewhere in the archives. . .


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## Wingshooter

It is the length of the draw. Two tubes will contract the same speed as one tube. But it will carry twice the load of the single at that same speed. All things being equal. The reason the single shot the same is I could pull it a little farther with ease. If doubles or even triples shooting the same weight as singles you would think they would be twice or even three times as fast.
Another thing I noticed is that the 1745 single tubes after they are broke in seem faster. They are easier to draw so maybe I am just pulling a little farther. The rubber is softer to the touch. I read somewhere that rubber generates heat when it is pulled so I false draw the singles a couple of times and I think that improves my speed. Maybe that is one of those predetermind things I think it helps so it helps.
For me I see no reason to shoot thicker and heavier stuff where you pull so hard one eye bulges and you break wind. Just my opinion.


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## jskeen

It's been gone over in theory a couple of times, mostly in Dan's tech blog, and mostly with flatbands, but it's the same thing with tubes, but probably more so. My take on it, after looking over the math and doing some rough estimates and a few tests when I first got my chrony is basicly this. A given formula and shape of latex has a certain max speed of contraction at a certain temp. That's the max, as fast as it can move, with no load. When we cut it into bands, tie a pouch on it, and shoot it, subtract a certain amount from that, and get the no load speed for a bandset. The rubber itself is going to retract at pretty much that speed, no matter what weight of ammo we use it with, UP TO THE POINT where the ammo is heavy enough to start to slow the latex down.

The differences in projectile velocity below that point, are all a matter of energy transfer, not band speed. But, once you reach that point, the slope of the rubber contraction speed curve itself starts to change.

So, below that kink in the curve, the rubber itself is doing the same thing, it's just a question of how much of the energy is being used by the projectile, and how much is left in the bands and pouch after the projectile leaves. That's why a given set of bands will slap more with very light ammo.

But, the kicker is that the heavier the bands, ie the more rubber you are stretching does not increase the base contraction speed of the bands themselves. It moves that kink in the curve out farther, ie lets you shoot heavier ammo without actually slowing the contraction down, but it does not speed up the contraction itself.

So bottom line, If you want to shoot light ammo for a long time, shoot light bands cut long. If you want to shoot light ammo fast, shoot light bands stretched farther. Tubes seem to work pretty much the same way. The only reason to use doubles or heavy tubes is if you are shooting really heavy ammo (like 1/2 lead or larger) and want max impact with it. Otherwise you are just causing yourself hand problems down the road and getting little or no return on the extra input.

As always, YMMV!


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## Wingshooter

One thing I should have mentioned was the temp. It really makes a difference with these black tubes. It was hot out there yesterday afternoon when I got 200 ft per sec with single tubes and 1/2 steel. I went out this morning when it is about 70 degrees and the best i could do was 187 ft per sec. I think a more realistic number. Still you can get a lot from the single tubes with very little effort.


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## Dayhiker

Now, Bill Herriman has stated that many a rabbit has been taken at 150 fps. So I take it that single 1745's and half-inch steel balls are sufficient to hunt rabbits with (assuming head shots). This is out to 10 yds., right? What about 15 yds.? See what I mean? Where is the math that accounts for distance traveled/energy lost?

Put another way. If I want to hunt rabbits out to 15 yards, can I still use single 1745 tubes and drop to 7/16 balls? Assuming a 34-36" draw.


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## Wingshooter

Dayhiker said:


> Now, Bill Herriman has stated that many a rabbit has been taken at 150 fps. So I take it that single 1745's and half-inch steel balls are sufficient to hunt rabbits with (assuming head shots). This is out to 10 yds., right? What about 15 yds.? See what I mean? Where is the math that accounts for distance traveled/energy lost?
> 
> Put another way. If I want to hunt rabbits out to 15 yards, can I still use single 1745 tubes and drop to 7/16 balls? Assuming a 34-36" draw.


Only for you my friend would I do this.
I setup my crono in front of my catch box and shot from 25 feet ,33 feet, and 40 feet that is the edge of my patio. Single 1745 1/2 inch steel.
25 feet at the catch box - 178 ft per sec - 8.34 ft lbs
33 feet at the catch box - 170 ft per sec - 7.43 ft lbs
40 feet at the catch box - 172.8 ft per sec - 7.67 ft lbs
I don't know where the outer limits would be I don't have the nerve to shoot at my crono any farther away.
I am sure you could get a rabbit at 15 yards with this set up and it could be a rib shot.
When Dr Beeman first developed his air rifle he figured out with real world testing that it only takes 5 ft lbs to kill a rabbit.
Now here is what I have been getting at if you drop to 7/16 my average speed the other day was 198.5. 7/16 weighs 86.4 so my foot lbs was only 7.56 what have you gained maybe slightly flatter shooting but at the range we are talking about I don't feel you gain anything.
There is a limit to light tubes and heavy amo but I am not going to shoot at my crono from any farther I just don't have the nerve and I am not that good of a shot. Hey lets get Bill to do it.


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## Dayhiker

Wow! Thanks a million, Henry. That answers all my questions and lets me off the hook for having to look up Dan's math-heavy blog posts. All I need are some references as guideposts to familiar materials and you gave me that. Thanks again, man!


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## Wingshooter

I am with you on that. When these guys start on there computations my eyes glaze over.


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## jskeen

Wingshooter said:


> I am with you on that. When these guys start on there computations my eyes glaze over.


Hey! You sound like most of the students in my classes. Are you sure you don't work for GE?


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## Bill Hays

Very nice Roger. The difference is quite amazing isn't it?!
Looks like when pulling the single tube your draw is about 2-3 inches longer than with the cheek release of the double tubes... never ceases to amaze me how just a few more inches of draw _length_ versus a few more pounds of draw _weight_ produces so much more speed...
Almost every day I get orders for special HEAVY weight bandsets... for which I do oblige, but I do write the customer back that draw length is FAR more important than draw WEIGHT.

The example you show in this video pretty well proves that point... we need a "useful" video thread pinned!


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## Wingshooter

Bill Hays said:


> Very nice Roger. The difference is quite amazing isn't it?!
> Looks like when pulling the single tube your draw is about 2-3 inches longer than with the cheek release of the double tubes... never ceases to amaze me how just a few more inches of draw _length_ versus a few more pounds of draw _weight_ produces so much more speed...
> Almost every day I get orders for special HEAVY weight bandsets... for which I do oblige, but I do write the customer back that draw length is FAR more important than draw WEIGHT.
> 
> The example you show in this video pretty well proves that point... we need a "useful" video thread pinned!


I agree Bill. I know I was really surprised the first time I shot 1/2 from a single tube setup. The pull was so light I expected the ball to hit half way to the target. I can get my head around shooting 3/8 from singles but had no idea what you could get with heavy shot. I have to be getting all the energy out of this combination because you can't hardly hear it when it shoots. Hitting a can at 40 feet is much louder than the slingshot under my nose. My new moto has to be " Add more rubber all you gain is more strain."


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## Lee Silva

Rock-solid info, that's really good to know!!! Wow, thank you guys!!!


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## DogBox

Lee Silva said:


> Rock-solid info, that's really good to know!!! Wow, thank you guys!!!


Hey! Nice 'dig-up' info!

Heh! "...one eye bulges and I break wind.!" Has to be THE statement of all time! When you know you've reached YOUR limits - not the tubes!


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## Lee Silva

DogBox said:


> Lee Silva said:
> 
> 
> 
> Rock-solid info, that's really good to know!!! Wow, thank you guys!!!
> 
> 
> 
> Hey! Nice 'dig-up' info!
> 
> Heh! "...one eye bulges and I break wind.!" Has to be THE statement of all time! When you know you've reached YOUR limits - not the tubes!
Click to expand...

 :rolling:


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## Onyx

Wingshooter's demonstration is pretty conclusive.

Let's continue the experiment with even more experimental rigour. Here is what I propose:

Three good shooters, three Chronys, exact same setup, and temperature, ten meters. Single and double tubes (1745 and 1842)
firing 3/8, 7/8 and1/2 steel and lead. That's a tall order I realize.
The idea here is to record the AVERAGES of three different shooters with different draw lengths so that the rest of us will have a pretty accurate idea of what to expect.

I suspect that most of SF members are more into target shooting and plinking than to hunting, they are likely to prefer a longer flatter ammo trajectory than energy at impact.

The setup could be repeated with different flat band configurations (an even taller order!).

The resulting table would be highly instructive and serve as a reliable guideline for all of us. It would also dispell a few myths!

It just occurred to me that we could probably do all of this at the next ECST meeting. Would be great fun wouldn't it!


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## Smashtoad

I just read this thread for the first time...freakin awesome.

That bulging eye fart line made me laugh out loud in the cube farm.


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