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seatec guns

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.

dave

Dicentrarchus labrax
Jan 13, 2003
497
187
133
Seatec guns are made by Valerio Grassi, the founder of Omer. They are very good, with a lot of nice little features, but then I am biased as I sell them!
cheers
dave
www.spearo.co.uk
 

shaneshac

FIN TRASHER
Oct 8, 2002
1,874
178
153
44
Seatec guns are regarded quite highly by the italians.

They are quite high tech and are always at the pinnacle of development. you will need to check for the availability of spare parts etc.

Hey Dave, nice to have you on the forum. How is the new Rollergun. Have you tested it?

Shane
 

jorgetes

New Member
Jan 1, 2004
17
0
0
51
Hei all,

Sorry for this post, just want did to ask Dave if you have any problem with the email shop.
Shane, Today i have used a 6,50 mm demko(shark fins)shaft with 170 mm long in the tahiti and i,m very surprised with the accuracy on shot.
I was in a place with 25 meter deep.Was in the surface when i saw a very nice anjova in 5 meters.She was eating like a hell.
I have fired in about 1 1/2 meter deep.She was pierced on the head just in the seem point that i was aiming.I never aim at with any kind of point, but in this case want did to know the accuracy with this kind of shaft in the tahiti.

I recomend!!:D :D :p

I did not have the camera, but i make a mobil phone picture.I ,ll try to send it.She was 7.50 kg!!

Thanks and sorry for my english!!:duh
 

shaneshac

FIN TRASHER
Oct 8, 2002
1,874
178
153
44
Nice one Jorge,

Hey there are loads of ppl waiting for your response on the gun.

Are you selling it or not.

Did you receive my phone number?

Show us the pics please ;)

Hasta luego luca!!!!!
 

dave

Dicentrarchus labrax
Jan 13, 2003
497
187
133
I have been testing the 66cm and 86cm roller guns
They both work very well, and have the range of a much larger gun, but this does come at a price.
If anyone would like more info please pm me
cheers
dave
www.spearo.co.uk
 

shaneshac

FIN TRASHER
Oct 8, 2002
1,874
178
153
44
Hey Dave,

When is the Bluewater hunting section appearing on the site?

Do you stock the Seatec Gabbiano or the Seatec Albatros?

What about the Seatec Bodyboard Style Float.
 

harpune1

Harpunetti
Apr 8, 2004
145
10
0
36
i would love to hear more about this roller guns, where to get those?????????????????
what is their advantage?
 

harpune1

Harpunetti
Apr 8, 2004
145
10
0
36
it should have more range then?
or just more power on short distance ?
has anyone used it?
where can i get it?
 
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Reactions: Alison

dave

Dicentrarchus labrax
Jan 13, 2003
497
187
133
Roller guns are a way of getting more power out of a shorter gun. The rubbers continuing under the barrel give the equivalent of a longer gun, as they act on the spear for a greater distance (the kinetic energyof the spear is equal to force times distance it is applied over). The Seatec 86cm has similiar range to a normal 100cm gun. The downside is the increased bulk and weight of the gun.
For a better description of rollergun physics look at http://niko.bonitofreedive.org/
cheers
dave
 
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Reactions: Alison

Fondueset

Carp Whisperer
Jul 27, 2004
4,604
734
203
15
I get it

Basically the rubbers are accelerating the shaft for a greater precentage of it's travel along the gun because of the greater elasticity of a longer rubber compared to a shorter one. cool
 

fuzz

Hawaiian transplant...
Sep 9, 2002
995
73
0
43
Probably a re-iteration of what you just said...

The principle is based on the fact that a traditional gun has an effective band usage only equal to the amount that it stretches/ This means that if a 100cm gun has a relaxed band length of 30cm(just a rough example), then it has power potential of the remaining 70cm band stretch. A roller gun will anchor a band(obviously longer than traditional band) under the barrel so it will stretch for 90-100cm of the barrel length(from near muzzle to notch).

Therefore, the rollergun will have 20-30cm more band pull for the same-sized gun... or a shorter gun will have the same power as a longer model.

Often discussed it with others, but never had the opportunity to try one out in person. :(
 

peskydor

New Member
Jul 19, 2004
145
11
0
Monte's (nick's) site gives a good explanation of the physics. However, dave did not restate this correctly. Kinetic ENERGY is not FORCE X DISTANCE. This product is defined as WORK. ENERGY is defined as the product of MASS X VELOCITY SQUARED / 2.

This is only a nitpick and does nothing to detract from the clever idea of the roller gun.
 

GilbertG.

New Member
Jul 28, 2004
113
23
0
Good pickup peskydor. Clever I agree. Practical? Maybe/maybe not. More moving parts mean a higher suceptibility to wear/breakage/malfunction. The delrin rollers must do a good with the wear issue though. We use it on aircraft and it supposedly lasts forever. Aesthetics seem to suffer (in my opinion). Another problem one could anticipate might be a faster rate of deterioration of the rubber if it remains in tension preload when the gun isn't loaded and the fact that they are pulled around the rollers. Interesting to see how well this gun will sell. I'm tempted to build one and test out the concept myself...
 

GilbertG.

New Member
Jul 28, 2004
113
23
0
Thought about it a little bit more.

Good: Higher power (compared to a gun of equal length), faster tracking/training (compared to a gun of longer length), less bending of the barrel since it is shorter than a longer gun of equal power and that the portion of the bands below the barrel counteract the bending.

Bad: Higher recoil due to higher power and smaller gun mass.
 

Murat

Promethian
Jun 21, 2002
2,982
159
0
38
66cm rollergun should have perfect use for the cave grouper hunting, but its bit pricey...
 

peskydor

New Member
Jul 19, 2004
145
11
0
I pulled two Biller guns off the rack. One gun has a pull of 43 inches (rear of muzzle to sear box) and the other 26 inches. Measuring the distance from slack rubber (wishbone) to sear box, both of these guns have a tension span of 73% of total pull. Looked at another way, a full stretch is 1.37 X the actual stretch. Therefore, a roller gun should have 37% more stroke with the advantage occurring in the final stretch so to speak. I'm guessing that the average force applied during the final stroke is about 18% of the force at full tension or about 37% of the average force applied when discharged. This should result in an approximately 37% velocity beyond what a conventional gun would induce. However, since kinetic energy is related to the square of velocity it seems to me that the extra energy imparted to the shaft should be 1.37^2 or about 90%. Adding a second rubber to a conventional gun should give it 46% more velocity than a single rubber roller gun.I'm probably missing something here but.......One thing may have to do with time and acceleration force. Since the shaft is traveling faster as it goes down the track the increment of time that the accelerative force is applied is smaller during the final inches of travel than at the beginning. Since velocity = Acceleration X time the actual velocity imparted to the shaft may be less than expected. However, this same idea, if correct, would apply to conventional, multi-rubber guns as well. Thus, the guesstimate number may hold water a bit longer, at least until some objections are raised.

I'm editing as I go along, eg when more issues arise. Typically, when I sleep on it I change the whole thing (G). Anyhoo, how come that one expert, Monte, says that roller guns have minimal felt recoil (barrel lift) when Memo (the guy from Colombia) has added wings to suppress recoil? Something doesn't add up. Admittedly, adding wings (mass) is more convenient with a wood gun than a tube type. At least, the flotation isn't impaired. This may be a gray area of contention.
Pesky
 
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peskydor

New Member
Jul 19, 2004
145
11
0
Hmm, velocity is not V = AT and distance is not S = 1/2 AT ^2? ? Since when? Is that a special relativity thing?

Edit: OK, I get it, a joke. You did give me a laugh, thanks.
 
Last edited:

Fondueset

Carp Whisperer
Jul 27, 2004
4,604
734
203
15
Relativistic Rubber

Does this mean these guns function at a 'right angle' to time? Sort of 'atemporal' as it were. Among other things this would certainly reduce/increase wear on the parts - since they would allways allready never/allways have been fired - the gun would then exist in a sort of perpetual state of ... er.. never mind. Been diving in really cold water..
 

peskydor

New Member
Jul 19, 2004
145
11
0
Gilbert, yes, it looks to be a fun project. Need to take another look at the location and arrangement of the shooting line. I'm not used to having something bulky fastened underneath the barrel unless it's a reel. Well, my old Potts gun had a bracket with CO2 float in about the same location but the muzzle itself wasn't obstructed. "Monte" and "Memo explained a lot of that stuff but......gotta check it out for a Winter project.
 
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