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Eurogun band poll

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.

Bands number vs bands diameter preferred combination

  • One 16 mm

    Votes: 3 14.3%
  • Two 16 mm

    Votes: 2 9.5%
  • One 18 mm

    Votes: 4 19.0%
  • Two 18 mm

    Votes: 0 0.0%
  • One 20 mm

    Votes: 12 57.1%
  • Two 20 mm

    Votes: 0 0.0%
  • Other combination

    Votes: 0 0.0%

  • Total voters


New Member
Sep 13, 2003
I have been looking for information regarding the power (kinetic energy) of the different combination of number and diameter of bands used in Euroguns. I understand that different fishing strategies require different setups. Anyway, it seems to me that even under similar conditions, there is no clear preference for a given combination. I think it would be interesting to know which particular combination of number of bands vs. diameter is most common, if any. Finally, I would like to ask you a question. It is correct to say (assuming all other factors are identical) that two 16 mm bands can produce about 30-40% more power than one 20 mm band? Thanks for your comments and votes.
hi Mate

1 20mm band is by far my favourite and it just happens to be that yesterday I got in the pool and did a little Iya pool testing.

The gun I was testing was my Rob allen 110 setup was, 7mm shaft 1.4m long, single 20mm band and dyneema shooting line. Before I got in the pool and my reason for testing was to work out if I should use a single wrap or double wrap of dyneema. I had it setup with a single wrap which from the muzzle to the speartip measured exactly 4.9m.

I jumped in the pool and loaded to the 2nd notch I was thinking that no way will it even shoot close to 5m but I aimed and fired suprisingly the shaft hit the end of the line with very little drop, there was also a little bit of a jerk from where the spear tried to go further by pulling the handle out of my hand.

I did a few more test shots and decided that I should stick with my favored two wraps of line for shots on fish that are slightly more vertical.

Conclusion 1 20mm band with that setup more than impressed me for such a small gun.

Im afraid to pool test my 150 in case the shaft hits the end of the pool which has happened more than once with an old 140.

Theory of a speargun

Energy stored in a band is
E = elastisity*Rubber length*(pi*diameter^2)/4 *
((Barrel length-Rubber length)^2/)2

For the same band and barrel length, 1X20mm will store 400 energy units, while 2X16mm will store 2X256 =512, or 28% more;
3X14 will store 588, or 47% more than 1X20 and 14% more than 2X16.

At the same time, it's important to have the correct rubber length, as energy depends cubically on the rubber length, being maximum exactly when Rubber length =1/3 of the barrel length.

Ivan, you should test the accuracy out - maybe with a bottle or anything handy.

I'd be very interested in seeing your 10-ft. accuracy between single & double bands. I'm having trouble with my RAs unless I go to single 16mm with 6.5mm shaft
I solved the single or double wrap issue differently...

Since i have reel i can take extra line out from it whenever i need and make an extra wrap....;)

Fuzz only problem is that the pool bottom is not flat it slowly slopes down so I cant measure 10ft accurately, I just like seeing the spear travel flat then dropping suddenly.


Great!. Any reference where I can learn about the "physics of spearfishing"?

If the pool slope deeper on one end, take a lead weight and place a mineral water bottle filled with 70% of water 30% of air and close the cap. Float it on the same "surface to your gun aiming depth". This way you get a horizontal shot. 70% of water in a mineral water bottle will make the bottle still float straight up and heavier, good for target shooting. If you want, take off all the label. Wrap around the middle of the bottle with 2" (5cm) dark color duct tape as aiming zone.

Let us know how is the accuracy test with 2 x 16 bands...:p
I use a beuchat 96cm reel gun and found the single 16mm grossly underpowered. 2x16mm was to bulky and acuracy sucked. I went to a 20mm Cressi megaton bands from deeperbly and LOVE them. acuracy and power improved and it feels like a new gun.

What about double power 18mm on OMER Alluminium with 6.5mm shaft??? I heard from one of the form its deadly accurate. Hard to belive ha????

Interesting. What is deeperbly? Is it online?
oops! Edit. I relized too late you meant deeperblue. By the way, I read the post and saw the pics of the jbl rail you added to your Beuchat. Are you happy with it or would the Wong rail (?)be a better option?
Last edited:
it ain't no rocket science! Just look up Hook's law in some high school text book. BTW, by Barrel length I meant the length of the stretched band, when gun is loaded.
Dear friends,
I have 104cm wooden barrel gun ,6.5 mm shaft and 20 mm full black sling bands,which 20mm sling band or which double 16mm sling bands (euro or elsewhere) could you advise for me?
Hello Cingene,
I was born in Karsýyaka,if you have lived in Ýzmir you must know the difference.My office is in Karsiyaka but my I'm living in Yakaköy_Bornova(at the mountain).I think once upon atime you have lived in Ýzmir.
Greetings fromÝzmir to California..
Dr.Aydýn Mevsim
Doesn't we already had a member whoes nick name is Amevsim from Turkey??? Any relation???
Hello Murat,I'm the same man, with the amevsim nickname I've asked somebody in the forums in Italy that how and where can i buy a wetsuit from Verona,my wife will be there in next month for three days etc. etc. ,but than i take a message from deeper blue that shopping must be online and after that experience i can't reply any message with amevsim,then i take another nick aydýn and go on..
I'm sorry for the situation,but i think that i have no fault.
Dr. Aydýn Mevsim
Yeah sure you have no fault doc. I just wondered if its the same person. Have nice fun:D
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