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spear length

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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S

sickbugs

spearo
Jul 5, 2005
341
18
0
40
any rules to follow for this? ive been thinking about rebuilding my beuchat to be a 110-115 cm gun (teak barrel) because of a change in my hunting, and wondering what length spear i should buy for it.
 
stock spears are normally 30/40cm longer than the barrel. Some guys use also extra-short spears: they say they go straighter in distant shots, but this has misadvantages too. Better go stock: barrell size + 30/40 cm is the best set up for me.
 
I got a thing about this one.I like to go up one more size.That is in a 90cm gun I use a spear from a 100 or 115cm gun.

I find that the tip being nearer the fish and thus reducing the range outways any disadvantages. The thin spear sticking out the end does little to slow down tracking and a longer spear, I find, flies truer. Slightly slower velocity is countered by the reduced range and the increased momentum improves hitting power.

This is with regard to using band powered guns against freeswimmers not reefing or flatfishing.

My opinion for what it's worth.

Dave
 
I think the idea is that the overhang of the spear counteracts the sag of the spear over the barrel of the gun, sounds logical to me. By that reasoning for a non railgun the overhang should be the distance between the muzzle to the wishbone / 2.
Less of course for railguns as the longer spear would sag beyond the muzzle causing it to bend upwards off the rail which maybe or maybe not cause an exessive oscillation when its fired?
 
This subject of tip overhang came up just a few days ago on Spearboard. FWIW, there was an article on the subject by gun maker Steve Alexander in Hawaii Skin Diver, and I summarized its major points. Here is a copy of that post.
****************************
FWIW, I found that HSD article on overhang by Steve Alexander. Here are some high points.

Its a matter of personal preference.

A heavier shaft needs more band force to attain the same muzzle velocity, but a heavier shaft will also go farther.

Heavier shafts will increase recoil.

A long overhang is easier to see and aim for many divers.

A short overhand will be more maneuverable in conditions such as thick kelp or caves (or rigs).

He doubts that most divers would be able to detect a difference in performance with as much as 15% difference in length.

The best way to determine what works for you is to experiment.

Spear shaft straightness and tip design will affect accuracy and range far more than shaft overhang variations.

You are not likely to see much variation going from one extreme to the other.

So sayeth the Lord.
 
Bill McIntyre said:
Spear shaft straightness and tip design will affect accuracy and range far more than shaft overhang variations.

You are not likely to see much variation going from one extreme to the other.
Click to expand...
Well thats probably very true, one could argue the maths or physics of it all day but when it comes to the bottom line, its the guy holding the gun who knows where the spear is likely to end up as long as he has practiced with the current set up (according to a good friend of mine)
 
thanks all, i had heard that a longer spear gave better accuracy, which is what got me thinking.. im gonna try out the spear from my 100cm on the 75, see how it works.
 
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