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Speargun purchase, help!

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.
The C4 is possibly the most seductive gun around, no doubt. I am very happy that you like it. For me would not work because it cannot be taken apart for travelling. I have also some technical reservation though. After having gone through the 7 parts engineering studies on arbaletes from Dapiran and other engineers I do believe that the rail is very important both for precision and speed. As the spear leaves the release mechanism it goes into a vibration/flexing state caused by the load induced by the bands. I actually so the picture taken with a very fast camera, quite amazing. The drag in the water is function of the diameter and a vibrating spear offers a diameter much larger than the actual one, the friction increase more than a spear stabilized by a rail. That is why, given the same weight a thicker shorter and stiffer spear is faster and penetrates more than a thin long one.
The rail stabilizes the spear in the most critical moment of the change of energy from potential to cynetic. The moment is explosive and the picture shows it.
The rail counter acts also the tendency of the spear lifting by the articulated wishbone which engages in the slot cut in the spear. Again it is showed in the picture and make sense if you see the vectors of the force at play.
That's the reason why the shark fin spears and rope wishbones came about.
Cheers
Giovanni
When using a articulated


 
I have the impression Omer tests pretty thoroughly these days - just judging from how long they have prototypes out there before they go into production.
Interesting about shaft vibration and rails. I've thought for awhile it would be interesting if a gun could be designed that accelerates the shaft with a very controlled curve - similar to a compound bow. It would have to be a roller gun with some kind of assymetrical rollers - hard to design and probably ugly.

Along different lines I have a little Riffe MT0 which I've rigged with a 1/4 x34 inch shaft (6.35m x 86.3cm) - which is the opposite of how these guns are usually rigged (heavy shafts and lots of bands) with a couple of 5/8 (16mm) bands it shoots beautifully for smaller fish out to about 3 or 4meters. very accurate and no recoil. I like it because it is very small and extremely sturdy but still has pretty good range.
 
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Giovanni, one last thing: if you plan to often reassemble and disassemble the handle from the barrel, I think you should buy a couple of spare junction pins (spine di giunzione). I think they're made in grivory plastic and likely to get broken (and small enough to be easily lost). For the same reason I would avoid carbon barrels (smonta e rimonta può creparsi, ho paura). Take care!
PS: my "pusher" says the Cressi Geronimo will not be available before the end of March...
 
Yes, I would also buy a couple of spare pins but no carbon gun. Carbon fiber is too delicate and prone to chipping/cracking. In my opinion is not a very good material for spearguns. Great for fins though.
Cheers
Giovanni

 
FYI - the Omer Cobra's modular grip/trigger assembly is designed to be easy to remove for travel. The pins are stainless steel- there are two that hold the assembly and a third small one for the line release. The 100cm guns and longer are designed to take two bands and the teak stock absorbs recoil well. The mech is the same as the T-20 and Master America so it's reliability is well established.
 
The Caymans are out in Italy!! The 100 Cayman HF is about 200 Euro. I guess one will be mine next week. Overall on the paper the Cayman HF is almost as good as many wooden one but a lot cheaper. It comes with a decent reel and spear. To get it into a powerful mode all I need to buy is an extra short 7mm spear and another circular band.
Overall seems a very good bang for the buck.
http://www.acquasport.com/indcat.htm
Cheers
Giovanni
 
I will. Unfortunately I won't have any other gear to get in the water in Italy. I don't think I will stand waiting to trying it out. I may end up just going to the beach, submerge it and shoot it in the shallow clear water. I could get a pretty good impression of the potential. Mind you, it can also be quite embarrasing!
Cheers
Giovanni



Fondueset said:
Give us a review if you can!
Click to expand...
 
It is mostly illegal to spear fish here in Michigan. I usually bring a gun along and practice in shallow water at the end of my dives. During the winter there is hardly anyone around - and the few who are don't seem much interested in talking. Probably they think I am insane freediving in 3C water! Its fun though and helps develop skill for when I get to places that are more spearing-friendly.
 
Forgive the Off Topic Chris, but what does "mostly" illegal mean? I seem to remember you told me about bluegill, carp and pike being legal to spear (I'm just curious because I enjoy lake spearing too).

One more thing that's almost on topic: I was looking for a T20 allu 75 centimeters for my sister's son, who turned 16, but it's impossible to find it here in Italy where it's made. Sold out by all shops. That's disappointing. I'm switching to a Comanche 75.
 
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Carp, suckers, Gar and bowfin - all not too good to eat. In fact noone eats bowfin. (probably detectable with a geiger counter - cool looking though )Also all too easy to spear - carp would be the most difficult probably around here. Over in Wisconsin (where Jon is from) they can spear panfish as well. From shore or with a bow you can spear more species than with a speargun. This, I think, is because spearos are the smallest demographic - so they get punished for the excesses of the rest!
 
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