Why pay more?

[GALADION]

Hi there!
This is my first post in here and I would very much enjoy being part of the “bubbly” gang.
I spearfish about a decade and I would like to pose a question concerning the barrel flex. Everybody using euroguns when faced with this problem turns to carbon-fiber or wooden guns which are very expensive!
For a month or so I have an idea which seems to me both effective and cheap. What about inserting into a standard aluminum barrel an aluminum bar (though I can’t figure out which shape would be better)?
This way I think the barrel would be completely stiff and still lightweight.

Any comments on my (stupid?) idea will be most welcome!!

 

[Pablo]

An aluminum bar may add more weight than you expect... and is not that cheap too!

But a plate just the width of the barrel internal diameter, set up in vertical position inside the barrel and hold in place with foam spray has already cross my mind: since I got a carbon RA and...

A carbon plate will do the same.

Better if your insert is cross profile to avoid the torsion forces when trying to bend a plate.

 

[GALADION]

Thanks pablo!
Your idea is great and I will try it out. I'll let you know if it works.
Anyway I see that nobody else was interested.:hmm It makes me wonder...Maybe I should find a better job too and buy a carbon-fiber barrel

 

[Greekman]

hey galadion i see that your located in greece? do you do alot of spearing there? if so where?

i am interested because i am going to greece for the whole summer. (i live in the us)

 

[GALADION]

Hey, that’s a surprise!!

During winter and spring I spearfish every Saturday or Sunday.
During summer and autumn, at least 3 times every week. I dive wherever there is a coastline, but usually in the Saronic Gulf, in Pelion and in Halkidiki.
But I would suggest you not to be very excited about the fish population in Greece or their size. You have to dive under 60-70 ft to shoot some descent fish!
Anyway are you of Greek origin? I was born in Rochester NY but my parents left when I was 2 years old. Technically though I am an American citizen!

I hope to read from you again Maybe we can arrange a spearfishing meeting in the future.

 

[Cingene]

how about just using a thicker I/D aluminum tubing?

 

[GALADION]

A friend of mine tried that out but under the stress of two 19mm bands the barrel bents slightly. I want to make a barrel which will be stiffer than a carbon-fiber one and after making some calculations with my brother we came to the conclusion that the thicker barrel doesn’t offer the support to withstand the load of 2 or 3 20mm bands on a 110cm barrel.
The problem is to find an aluminum plate with the proper profile shape which along with barrel itself will provide an absolute rigidity for the kind of load mentioned above.
If I don’t succeed eventually I‘ll convert to the carbon-fiber cult !!

Anyway thanks for taking the time to reply to my post!

 

[Cingene]

well now that is a horse of a different color. i would use stainless steel barrel.

 

[Russell]

Why so much power?

With two or three 20mm bands, you are putting a fair amount of stress on a 110cm barrell, that might not have been originally designed for what you are now using it for. So I was wondering what you were intending to shoot with this gun because you seem to have a lot of firepower there?

The reason I ask, is that it is very possible to do what you prescribe, in that you can implement internal reinforming in barrells such that the barrell is correctly braced against the direction of the force. When barrells flex, they actually flex about 3 quarters of the way towards the muzzle, the don't bow uniformally accross the barrell beween handle and muzzle. So what you would actually do, is to insert a brace into that component of the barrell. The brace could be another tube, but a better mousetrap would be a rectangular piece of alumuminum with the correct diameter.

Having said this, I am not clear to what end you are wanting to do all this work. All gun desigs have inherant trade offs, if its shorter, its more manoeveralble, but lacks range. If its longer, it has more range, but is harder to load. etc etc etc. Most guns are designed to have the appropriate stopping power for a given configeration at the range they are designed for, so over-engineering this gun, might be a lot of trouble for little overall gain. It might be better to basically select a longer gun, that provided other advantages vs. potentially overpowering a shorter gun where you get neither.

 

[Pablo]

An euro gun loaded with 3 20mm rubbers is an attempt to kill yourself or you dive buddy.

-the standard trigger mechanism become an hazard with twos 20mm rubbers... some before that.

-Those are light guns, and because of the laws of physics, the more power you apply to the spear, the more your gun will recoil... because the handle is at the end of the barrel and you aim on the front of you, you have a good chance to offer yourself a brand new nose and a full set of gold teeth.

Look at the blue water gun, one that I know of weights 18 pound for 70" and will hold 9 bands...

-All this power is apply to the spear... a good chance is that is not rigid enough. once you shoot the spear wobble and if it doesn't bend, he will have no accuracy. Some guns have an enclosed track to avoid that.

Guns holding 3 rubbers of 20mm are massif and heavy, using thick spears, wings and a pain for normal fishing... but excellent for blue water or satisfy your ego.

Have a look at Mullin 158kg marlin... with a 120cm escalpez and single 20mm rubbers: The spear went right thought the fish! and wasn't a "tip on the fish" shoot. The current WR (137kg I think) was as well shoot with an euro!

Is not the power of the gun... but your ability.

 

[Russell]

Black Marlin

Good point. Pablo. There are substantial fish that have been taken with single or dual rubber guns.

However, I believe the world record for black marlin is a lot higher than the 158kg fish you mention that Mullins shot in Mexico. I believe, that its more like 260! However, the point you make is still valid, it was taken on a Rob Allen Railgun with a single 20mm rubber (I think).

http://www.freedive.net/ibsrc/fish_pgs/b_marlin.htm

 

[Pablo]

Striped marlin, not black marlin! and both fish was taken in NZ. Mullin fish is waiting the confirmation for WR... I hope because he deserves it!

I use a RA 130 with 20mm and sometimes a second 16mm (with 7.5 spear)... is more than plenty for 99% of my spearing.

However, for some trips we are planing to go for BF and marlin (we have striped, blue, black and broadbill in here) I will try to use something more powerful: maybe a custom project for the winter?

 

[GALADION]

First of all I'd like to thank all of you for your advice!

Now I will let you know my intentions which drove me to such a project.
I do not intend to spearfish with such a gun but I and a friend of mine, both fed up with the carbon-fiber craze her in Greece, started our own weird:duh competition to make a bad-ass gun, which will have the biggest possible range and accurasy BUT with a tight budget (no more than 200 euro for the whole gun) something like the salary cap in the NBA.
So far we have made a couple of guns each,(sometimes he wins sometime I win) but we have reached to a point where is difficult to achieve our goal without taking extreme messures!
On the other hand we have benefited from this competition by improving the guns we realy use for fishing without spending a fortune for the same results (or sometimes better!)
Anyway THANKS A LOT for all the advice and in return in the near fututre I will let you know of some helpful and CHEAP tricks!
Thanks again!

 

[Greekman]

hey galadion i see that you get to spearfish pretty often so thats good. and yea i know about the fish in greece they arent too big and are small in numbers but o well. its more of a challenge for us spearos. and yes i am of greek origin my parents were born in greece and then came to america where i was born. Sure that would be cool if we could spear together sometime. I am leaving for greece june 21 and i will be in karpathos( a small island next to crete) for the whole summer