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One of my favorite flat bands are ordinary Alliance #107 rubber bands, available from most office supply stores in the US, though I buy mine from Amazon.com. They are cheap, require no tricky cutting and last a long time. Are they good enough for you? Good question, so I decided to do some tests to help you decide.

For comparison, I used two identical frames, my own design La Cholita in half inch plywood. One frame was banded with #107s and the other with .050 food grade latex from RubberSheetRoll.com cut the same width as the #107s. Both bandsets were fitted with Performance Catapult's (Jim Harris) pouches. I tied them on with thin strips of TB Gold in an OTT configuration and 8 inches between the pouch-tie point and the frame.

The first step was to fire 25 break-in rounds with each slingshot. I used .375 (9.4 mm) lead balls, and got a bit of hand-slap with both, indicating there is more energy available. Then I measured my draw-length at 34 inches, and using a digital fish scale measured the pull strength at 14.08 pounds for the #107s and 11.44 pounds for the latex.

Next I set up my speed test equipment, consisting of a metal chair with a wooden stick affixed to the back and a clothespin to hold a 5x8 inch index card located exactly 10 feet away from my catch box fabric. Then I placed my Acer Netbook on the chair and using Audacity, I recorded the sounds of a dozen or so shots from each slingshot hitting first the 5x8 card and then the cloth backstop 10 feet away. Then I transferred the files to my big computer and read the files to measure the elapsed time between the two strikes. I entered that information into a spreadsheet and calculated the speed in fps for each shot and finally got an average speed and energy. Here are the results.

#107
Average for 10 shots = 173.87 fps, 5.03 lbs/ft energy

.050 latex
Average for 10 shots = 183.95 fps, 5.60 lbs/ft energy

So far, no surprises. I expected the latex to be faster, but was pleasantly surprised to find the #107s to be as fast as they are.

Next, I will shoot both slingshots until the bandsets wear out or break. Past experience tells me to expect about 300 shots from the latex and more from the #107s. Every shot is recorded, so for the first time I will have an accurate count. Whichever breaks first will be replaced with a set of Tex's Field bands, and I will do the same speed, energy, and longevity tests on them, for comparison purposes. Note: Everyone already knows that Tex's bands are as good as it gets, so there really is no need for me to reinvent the wheel.

Henry

14 August, 2011 - The left side latex band broke at the pouch after 390 shots.
15 August, 2011 - 490 shots total on #107 bands. Very light scuffing at fork. No tears.
16 August, 2011 - 600 shots total on #107 bands. No tears.
17 August, 2011 - Velocity test - 178.7 fps 5.3 lb/ft energy
19 August, 2011 - Band broke at 696 shots
 

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Discussion Starter · #7 ·
Maybe i missed it, how many rubber bands did you use, or was it just one whole band per side? this interest me alot for my BB shooting.
I use one band per side and trim to length. These bands are much too heavy for BB shooting. I'm getting light band slap with .44 cal lead. I use some scrap TG Gold (Thanks Dan, ZDP-189) cut 1/2 inch x 1/4 inch by 9 inches for BBs. It's more than enough.

Henry
 

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Discussion Starter · #11 ·
Rather than trim the band to length, you might try using the whole band with a loop at the fork end. This might add a tapered effect and add an extra thickness at a point where you tie to the forks. I was going to rubber cement this extra band area to eliminate friction between the two layers of rubber. I would probably try that type of rubber cement used for bicycle patch...maybe contact cement...not sure yet...Maybe others have tried this to eliminate friction between bands at critical contact points...(?)
Hey! You're getting ahead of me. LOL!

My friend AJW has a Flat Cat that is eating flatbands with gusto, I'm going to make him a set like that to try on it.

On my Panama Tipicos, I fold a portion of the band back and underneath to eliminate abrasion at the fork.

Henry
 

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Discussion Starter · #18 ·
Awesome bands, i wish that one day they will ship it to my country (Israel)... if so, i will buy like bunch of em!.

And thanks Henry
Since you have one of my Typical Panama Slingshots with 107 bands, can you tell us how they perform for you, and how long they lasted?
 

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They lasted for about 1000 shots (and i have been shooting with rocks only).
No doubt, those bands have no competition at all, they are cheap, strong and fast!
Also, if im not wrong, u dont even have to cut them with a roller or anything, cuz they are an office rubber bands, easy to attach..
Oh god, if any1 knows a source that ships some of these to Israel and accepts paypal, pls let me know!
Thanks for the report, Kfir. I will send you 5 sets of bands (10) uncut, and a fresh pouch next week, so you can make your own. You can send me $3.00 to cover shipping to the PayPal address that will be in the package.

Henry
 

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Discussion Starter · #27 ·
What's the active length of the bands? (Same for both?)
What's the maximum elongation for those bands? (Same for both?)
Both bandsets measure 8 inches between the pouch tie point and the frame. I don't know what the maximum elongation is, because I suffered a very nasty slap from a broken band while trying to see how far it would stretch early in my slingshot career. I use the highly scientific method of holding a length of band in my left hand and pulling with my right to my draw length, adjusting the hold points until it feels as if the rubber is near maximum. Then I measure how far apart my two hands are on the relaxed band, and that becomes the pull length for that material. I determined that #107s can be set at 7 inches for my draw, but that 7 inches offered no increased speed over 8 inches for me, and was a bit lighter pull, so I use 8 inches for #107s. The .050 latex can be as short as 6.5 inches and still give me full draw, but I wanted both slingshots to be as close to the same as possible.
 

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Discussion Starter · #32 ·
Today I'm shooting 107s with .50 cal lead. I expect to have over 400 shots on them before the day is over. Here are a few pics from the first round of latex tests.

Here is the tear in the latex band. This set of bands can be cut and retied, but I am retiring them from the test, because not everyone will be ab le to retie them and not every tear will be so close to the tie point.
Hand Gesture Finger Thumb Wood


This is the slingshot and a #12 steel can that I dented up a little with the .44 cal lead balls shown.
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Discussion Starter · #34 ·
Ordered a box today, should have them this Friday, can't wait to try them. I will post chrony results when I shoot them. Thanks Henry for a great post.
Philly
I'm looking forward to seeing the Chrony results. I believe my measurements are pretty accurate, but will be very interested in what a dedicated chronometer says.
 

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Discussion Starter · #36 ·
I recieved my Sterling 107 Crepe bands today from Amazon. Couldnt wait to try them. I am impressed. I shot around 30 break in shots at 10 meters then set up the Chrony. My draw length is only 27 1/2" so with 3/8" steel i was getting 153FPS Avg. I drew to approx 34" like Henry does and I got 173FPS Avg. 457 lead was only at 135FPS at my draw length and 153FPS at 34" draw.

Working length was 7 1/4", no hand slap at all. I used my EPS for this short test.

I will definately use them for target with the 3/8" steel but I have recently tried .050 latex 7/8X5/8X7 1/2" long and get 185FPS with the same 3/8 steel and 165FPS with .457 lead so will stay with that for Hunting,

Can't beat the price for a 107 band set and Henry has already seen good life so I say give them a try. With my latest cut of .030 latex I am going through a set of bands every other day so this is a great alternative.

Thanks Henry, great find and thread.
Philly
Your numbers are pretty close to agreement with mine. I have only .25 steel, and no lead of the same size, but after seeing your measurements, I think I can pretty well trust the numbers I'm seeing with my Acer Netbook/Linux/Audacity setup. And from your numbers, it doesn't seem the Crepe bands are much different in speed from the Sterling.

Thanks,

Henry
 

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Discussion Starter · #40 ·
The velocity tests were a pleasant surprise. I expected to see a drop-off in speed, but instead got a bit more than 4 fps increase. That could be because I may have had an inch or two variance in distance between target and backstop. I can't say for sure about the first round, but this time I measured before and after shooting. At any rate, after 600 shots, the bands are lighter draw, slightly longer, and at least as fast. They just seem to get better with age.

Ammo - .375 lead balls
Velocity, average for 10 shots - 178.7 fps
Pull weight - 12.4 lbs at 34 inches
Length, pouch tie to frame - 8.4 inches

A couple of targets, steel on left, fresh beer can on right.

Tin Aluminum can Beverage can Tin can Liquid
 

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Discussion Starter · #43 ·
The #107 bandset broke on the right side 2 inches from the fork on the 696th shot. Power remained high right up to the last shot, which hit the target by the way, meaning the band broke while contracting. I consider that to be pretty good life, especially since they were drawn to near maximum on every shot. I will continue recording life and performance on #107s, but will post updates less frequently. I think there are a few changes I can make that will increase band life, without a large decrease in speed. I think making the bands a bit longer and holding velocity to about 160 fps with .375 lead will make a difference. I also am going to use the doubled under mounting method I use on my naturals to decrease scuffing at the fork.

My first conclusion is that the Alliance Sterling #107 rubber bands are good enough for plinking, target shooting, and almost certainly small game hunting. They require no cutting except to length, are cheap, and compared to self-cut latex, long lived. Give them a try.

Henry
 

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Discussion Starter · #68 ·
I think maybe slingshot_sniper was having a bit of fun, and meant no offense.

Just put together a set of 107s for AJW to try on his Flat Cat. I'll try to do some speed measurements on them before I turn them over. These are doubled at the fork and looped back, giving 5 1/2 inches of single band and 3 inches of double on each side. Break-in shots on my Dankung feel faster than the 8 inch pull singles.

Henry
 

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Discussion Starter · #74 ·
Yes, that does sound like a cool idea, but how do you manage the attachment in the middle?
I could see that being pretty cool on a ttf frame, but it would require a dedicated fork, the slot would be too wide for TBG, in a matchstick setup. You could probably do a wham-o style double slot that would work for the 107's tied back to themselves, or double TBG. Hmmmm. Might have to try that. Of course you are stretching both sides, so it might not hold in the slots at all.

All In all, I will probably continue to actually taper the bands with my rolling cutter, same as the tbg.
I'll post pictures tomorrow when I assemble another set for me. I feed the loop through a short piece of tube, then tie over the tube. I haven't tried it, but I bet industrial strength contact glue would work.
 

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Discussion Starter · #80 ·
Unfortunately, yesterday I got tied up with some of the more mundane aspects of living in Paradise (buying a new stove, groceries, running errands) and did not get around to taking pictures and speed testing AJW's new band set. When I got up this morning, I decided to build my own set, taking pictures all the way and put up a tutorial on my website. When I finish the webpage and get it uploaded, I'll put up a link. For now, I just couldn't wait to tell you guys how it worked out.

The bandset is 9 inches long, pouch-tie to loop, and the single section is almost exactly half that, or 4.5 inches for each portion. The pull weight at 34 inches is 6.8 kg/14.95 pounds, only one pound more than the single 8 inch 107s. The pouch is one of Jim Harris' superb die-cuts.

After a few break-in shots, I set up my makeshift chronometer and fired off 10 rounds. Frankly, I was flabbergasted! Shooting .375 cal (9.4 mm) lead balls, this roughly $1.00 bandset ran a 10 round average of 222.7 fps (67.88 ms), and was extremely consistent. The slowest was 214.7 fps and the fastest was 228.9.

I sincerely hope someone else who has a real chronograph will build a set of these bands and see if my measurements are accurate. It just seems a little bit too good to be true.

In the meantime, here's a shot of the bandset mounted on my Dankung Jungle Hunter II. The Dankung is far from ideal for this type of band, and keeping them dressed is an irritant, so in the next day or so, I'll have them mounted on a frame more suitable for them.

Henry

Azure Eyewear Eye glass accessory Electric blue Plastic
 

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I finally got the webpage done, but before linking to it, I wanted to run some velocity tests again, just to make sure that what I saw yesterday wasn't a fluke. It wasn't. 5 shot average with .375 lead was 223.6 fps. Just for grins I grabbed some .50 cal lead and fired a few rounds. I only recorded 4 shots, but I was amazed at the results. 3 shots were over 191 fps and the 4th hit 181.5. That's 14 lbs/ft of energy!

There definitely will be more experimentation with this configuration. I'm going to try making the single portion a half-inch shorter, which will give me a little extra on the looped end so they can be tied on a regular OTT frame and still be half of the bandset. I'm thinking (hoping) I just may be able to hit 200 fps with .50 cal lead balls.

Anyway, if anyone is interested in making a set of these, you can find pictures and instructions here:

http://www.panamaretire.net/slingshots/biombos/index.html

I really hope someone with a Chrony will make a set. I trust my numbers, but confirmation would be nice.

Thanks MJ. I didn't know that, either. I'll bet that's the point where my first test set broke.

Henry
 

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Discussion Starter · #90 ·
if you get 200fps from 107 bands with .50 cal lead .... I am sold.
I'm hoping. Find out this afternoon, maybe. AJW is coming over for a bull and slingshot shooting session, and we're going to speed test my newly mounted on La Chola (La Cholita's mama, slightly wider) bandset, and the set I made for AJW's Flat Cat. Here's a couple of pics of La Chola and her new bandset.

String instrument Guitar accessory String instrument String instrument accessory Fiddle
Wood Font Eyewear Fashion accessory Hair accessory


Henry
 

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