A Quest for the Ultimate Slingshot
by Vlastimil Zuska
Concerning slingshots I was woken from my winter sleep by a shattering window of my flat due to an unknown slingshot shooter. I live on fifth floor, so I remembered my boyhood beanflipper made from tire innertube and I wondered what kind of slingshot that shooter used. To my surprise I found that there are the five slingshot manufacturers and many considerable advanced models. So I decided, partly influenced by my profession, to undertake a rather systematic examination of commercial products. I tested in sequence eight store-bought slingshots (Trumark FS-1, Copperhead Desert Scout, Barnett Black Widow, Marksman Adjustable Slingshot, Trumark FSX, Copperhead Powerstorm, Barnett Cobra, Saunders Double Eagle) and various kinds of ammunition (glass balls 1/4", clay balls 1/4", steel balls 3/8" and 5/16", lead balls 3/8", 11.4 cm, 9.35 mm).
The method of testing:
Shooting at distance of 10, 15 and 20 meters, from every slingshot ten firings, paper targets of three concentric circles with diameters 10, 20 and 30 cm. After deleting the best and the worst hits I made average results. Of course I used uniform ammo, lead balls 3/8".
At 10 meters the most accurate was Trumark FSX (with sights), next one Double Eagle, Powerstorm and Marksman WR-3, at 15 and 20 meters Double Eagle, Barnett Cobra and Powerstorm.
The power was measured by a number of perforated pages of wet phone book fired from 10 meters. The number one was Double Eagle, next Barnett Cobra and Powerstorm.
The slingshot with single powerband is captured in an antinomy: the stronger bands, the worse accuracy. The medium bands offer better accuracy at shorter distances, but their effective range is small and the accuracy rapidly decreased with distance. Magnum powerbands, due to the recoil after releasing, have worse accuracy. That result was affirmed by a Greek group of research slingshot shooters (see www.bestguns.com). What way can lead from that trap?
The Manufacturers in principle choose three ways: doubling bands, stabilizers and pulleys.
The Doubling (used only by Saunders for Double Eagle, which incomprehensibly disappeared from their catalogue) of bands reduces the inner resistance (hysteresis) of the rubber and thereby reduces pulling power and also the recoil after releasing. That reduction results in better accuracy and more power, as Double Eagle confirmed. Theoretically another doubling would lead to still better results and at the end we would have a bundle of very thin rubber bands. May be an idea for producers. Basically the same consideration probably prompted some manufacturers to develop tapered bands (RP-2, RP-3 by Marksman, Powerstorm blue bands by Copperhead).
The way of stabilizers was chosen by Barnett (Cobra with one stabilizer, Pro-diablo with three ones /!/) and by Trumark (FSX-2000, FS-1 XFOA), following the same function as for bows and crossbows. Unfortunately that improvement simultaneously debases handling and storage. The final "word" in that story would probably resemble a porcupine.
The third way, way of pulley systems, also following the examples of (cross)bows. Till now there is only one representative - Marksman Laserhawk Stealth. The pulleys operate as a guide for bands, they reduce needful pulling strength, provide additional powerband stretch and thereby increase the amount of accumulated energy and especially eliminate after-releasing recoil or jerk by distribution of recoil into sides.
In theory the ultimate slingshot should be consist in double or multiple bands, in pulley system and a system of stabilizers. Because the outdoor equipments or sport and hunting market does not offer anything similar to it I had to choose a way of my own constructions. So let me shortly describe how I arrived at the sight of that ideal of accuracy and power. At the background of my quest was an image of slingshot as a handy weapon, so I drop the way of stabilizers.
My first model, baptized Goliath, had double bands (Barnett yellow ones). Pulling strength was too great and the slingshot was rather stiff apparatus. After few firings I got a crick in triangular muscle and I had to finish temporarily my research. Not even replacement by black Copperhead bands (for Desert Scout and Cyclone) and finally by Trumark normal pull bands improved the situation. The model did not overcame Double Eagle as to the combination of accuracy and power and confirmed above mentioned antinomy of strong bands and accuracy.
The second model - Big Ben, brought into play a pulley system with vertically situated pulleys (3.5 cm in diameter) and used Barnett bands again. Result? - the total fiasco!
Powerband stretch was longer of 12 cm, pulling strength increased from 9 kp to 12 kp, but the accuracy went to hell. The pulleys actually increased recoil.
The third model, named Red Hunter after my motorcycle Ariel from 1938 and according to its color, applied horizontally situated pulleys, which distribute band recoil into sides and actually eliminate it. The power remained the same, but the accuracy distinctly increased. However after about two hours of shooting powerband faded, its length extended from original 17 cm to 21 cm (measured in quiescent state).
The fourth model, Black Hunter, had lowered prongs and used black Copperhead bands. Almost a hit into the bull's eye! The accuracy was better than Trumark FSX and even Double Eagle on longer distance, the power was comparable with Double Eagle. For example I hitted a chimney of a hunter cabin three times from five shots at the distance of 30 meters. The chimney had a diameter of 10 cm and after my sixth shot collapsed.
The fifth model, Black Gulo (wolverine in Latin) used large polyamide pulleys and prong extension. With Barnett yellow bands the result was similar to the Red Hunter, the same power, but better accuracy. I also tested Marksman RP-2 bands: the accuracy at shorter distance was very good, but the power rather weak. Certainly it is not by chance that Marksman has produced for their Stealth stronger bands RP-3, moreover tapered ones. Unfortunately at present RP-3 is not on Czech market.
The sixth model, Black Window, was based on discovery that holding parallel to the ground, i.e. horizontally improves accuracy (that way of holding is recommended by Trumark and Saunders). Because personally I do not like that kind of holding, I decides to construct a mixed model with prong of vertically held slingshot and with a handle for horizontal holding. Naturally I used a pulley system. For additional increasing of accuracy I applied a windowlike prong. With the use of Trumark heavy pull bands I arrived at a combination of power and accuracy which overcomes Double Eagle.
In future I prepare examinations of RP-3 on the Black Gulo and the Black Window and Double Eagle bands on Black Bear (Alas, also Double Eagle replacement bands disappeared from Saunder's catalogue). Oh, I have not mentioned my seventh model. Just mentioned Black Bear has double bands and double pulley system, i.e. four pulleys in all (I tried Barnett's and Trumark normal pull). The slingshot is very strong, but the pulling strength still too great and the accuracy a bit worse than Big Gulo's. Probably by using two RP-2 I would obtain very effective "toy", still pretty heavy.
So I hope that I have not bored my fellows slingshot shooters and that we together would come to the Dark Tower of the ultimate slingshot.
101 00 Praha 10