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Rabitech

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.

defofthecrown

Morone saxatilis
Mar 8, 2003
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Two questions,

1: Is the muzzle for the Rabi. stealth detachable? I have put the gun in a vise (after removing the screw) and pulled on it as hard as I could bring myself to do before aborting. There was also a small amount of water getting into the barrel which I hypothesized was from breaking a seal between the muzzle and screw or muzzle and gun.

2: Are the carbon stealth components compatible w/ RA's? I would love to pick up a ra 150 barrel and chop it into a 60 and 90.

Florida freedivers told me a maybe? on the first Q and no on the second. But if anyone has experimented I would like to know what is possible.
 

fuzz

Hawaiian transplant...
Sep 9, 2002
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Hopefully Andrsn will see this thread or send him a PM ;)

He had a rabitech & used to swap out barrels & as I recall through an email, found that the barrel ID's were different.
 

miles

BORN WILD!!!
Supporter
Jun 13, 2003
1,486
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Hiya

I had a Rabitech grip fitted to my 1.1m Carbon RA. Needed a bit of work but fitted without too much hassles. Hope this helps.
 

defofthecrown

Morone saxatilis
Mar 8, 2003
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Miles, does need a bit of work read shaved down? I'd ideally like to change between a 120 stealth barrel and shorter RA alluminium lengths, not just make a one time switch.
 

miles

BORN WILD!!!
Supporter
Jun 13, 2003
1,486
393
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Will find out later today by rabitech whether the alluminuim barrel will fit with-out any mods. Just some advise, if you're used to shooting with a rabitech, i found that i tended to shoot high with the RA Carbon. A couple of rabitech owners who also owns RA have experienced the same. So before you go chopping up you gun, try and test a RA and see if you're happy with its accuracy as opposed to your Rabitech.

Both are railguns, so i don't know why my Carbon RA shoots higher that my Rabitechs. (i've been using rabitechs for about 1 1/2 years now)
 

Griff

Certified SCUBA Rider
May 7, 2002
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With regards to taking the muzzle off, it can be a real mission. (i'm assuming the rabitech muzzles are same material as the RA) the muzzle swells because its absorbs a bit of water, and ends up jamming into the barrel. if you really want to get it out, use a block of wood and smack it by running the wood along the rail. this eventually gets it out. the big problem comes to when you want to put it back in. getting it lined up properly is very difficult, and something i dont want to have to do again.
i have heard if you take the handle off an old RA, you have more chance of breaking it.

i wouldnt stress about the water from the barrel. if rabitech is anything like RA, the barrel plug starts a few cm's from the muzzle. the bit of water is from the space in between, and isnt really meant to be a proper seal.

miles, are you using the same sort of spear overhang with both guns? the difference may also be the lighter carbon barrel having more recoil?

cheers, and have a good weekend
mark
 

Rat Cunning

New Member
Sep 11, 2003
28
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Recoil Causes Guns to Shoot Low

While recoil is a major reason for gun inaccuracy, there is a widely held fallacy about its resultant effect.

Most people think that recoil as the result of overpowering is the reason a gun shoots high. This is, in point of fact, completely untrue and self evidently so.

While a speargun does recoil, in much the same way as gun ricoils and the front of it lifts up post discharge, the effect of this on the spear is to actually to lift the back of the spear, causing the front of the spear, to tip slighty down as it leaves the barrel. The reason for this is there is a slight delay for the gun to start rising, and the spear is more than half out the barrel (i.e. past its tipping point), by the time the effect becomes prounced. The net result is that recoil, causes overpowered guns to shoot low!!

A likely reason for your gun being inaccurate is that the rubbers on guns are different, or your spear length is different. However, the most likely suspect could be your wrap pattern, or the way your shooting line unfolds post release, and this is probably where there is a subtle difference.

Both of these guns are great all purpose guns, so you are lucky to own both !
 

miles

BORN WILD!!!
Supporter
Jun 13, 2003
1,486
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Hi,

Both guns are 1.1 and both spears are the same length. Both use 20 mm rubber and 7mm stainless spears. In other words both guns are still identical in set-up. Even tried interchanging spears. Put the original handle back on the saracen as well, but it is still shooting high. Any other ideas????

miles
 

Rat Cunning

New Member
Sep 11, 2003
28
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More data

Miles:

I must admit that this is rather unusual and I am at a loss for reasons. By exclusion then, it has to be the muzzle, or the line release mechanism, but I am loathe to say either of these without more facts. It might also be the weight of the guns themselves

How dramatic is the difference in height?

Is it repeatable, are they consistantly off by the same amounts?

And how are you calibrating the guns. Are you resting them on a bench in a pool and firing them into a target without shooting lines?

If you are not doing this, it is hard to get consistant data.
 
Last edited:

defofthecrown

Morone saxatilis
Mar 8, 2003
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Griff the barrel seal on the handle side does have a gap of ~5cm, and I assume the muzzle seal is probably similar. However when I invert the gun I can hear the water running throughout the length of the barrel. I tried to seal the set screw w/ teflon goop so I'll see if that works once i get her back in the water.
 

miles

BORN WILD!!!
Supporter
Jun 13, 2003
1,486
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Hi Rat Cunning

I've basically been shooting a railgun for more thn 1 1/2 years now. I own 75, 90, 1.1, 1.3 Rabitechs as well as the 1.1 Carbon Saracen and a 90 and 1.1 Picasso with rails attached to them. I've spoken to Rob Allen who suggested that it might be the way i'm aiming, or the barb could possibly be flared too much. Well, i've changed the spears (the RA had a RA spear to begin with) and still the problem exists. Regarding the aiming, well i don't really aim, i sort of just shoot from the hip. Very seldom do i miss with my rabitechs, but i find that the spear on the RA tends to shoot 5-10cm higher depending on how far the fish is from me. When shooting reef fish, i can normally see the white mark where the spear just clips the top of the fish. Normally quite easy to get kill shots with the Rabitech's.

The RA is extremely light gun. It floats in the water with a spear in it, fully loaded!!! I've tried sticking lead weights to the bottom of the barrel but that didn't help much.

The RA Carbon is a beautiful gun, very light and is a pleasure to dive with. Accuracy problems has become so annoying that i started leaving it at home. Even my friends who have borrowed the gun (they own Rabitechs as well) complained about the gun shooting high.

miles
 

andrsn

Just visiting...
Aug 26, 2001
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def,

Both the muzzle and the handle should be removeable from the barrel. I know I have issues with water getting into my barrel (rabitech) but still love the way it shoots. I've shot the same setup on an RA but notice the RA's tend to shoot high, like the rest of these guys. Not sure what's going on with that. Anyways, the aluminum rabitechs (at least the ones Aquiles and I have) will not adapt to the RA muzzles. The O.D. of the RA muzzles is too large to fit the Rabi barrels. The design seems absolutely identical, just not sure what exactly is going on there as well.

If you're trying to cut up a long barrel, obviously it'd have to be aluminum. All you'd need is the barrel plugs and you're set. Just make sure you put some xtra silicone in w/ them. ;)

Good luck,
Anderson
 

shaneshac

FIN TRASHER
Oct 8, 2002
1,874
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Use "Tiger Seal" on the barrel plugs. Its Hard as nails but yet is rubbery and will stretch and shrink with the pressure changes.

Silicone (like the one used in bathrooms) did not withstand a dive to 20 meters.
 

Dogmatrix

Deeper Blues pet
Jun 4, 2002
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Ok... the RA carbon shoots higher then the stealth carbon because it has a lighter muzzle.. the stealth shoots lower because the muzzle is a little heavier... hope this helps... you will also notice this while swimming.

Rob
 

Murat

Promethian
Jun 21, 2002
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As Rat cunning states, if muzzle jump berofe the shaft's gravitational point (approximately middle point) reaches to the muzzle it should shoot high. If it jums after the shaft's g. point pass through muzzle it should shoot low. As a result someone must observe with camera to see when the muzzle jump significantly.

Or other reason to shoot high may be wishbones apply pressure to the shaft too much to downward direction so tip of the shaft rises up SLIGHTLY but of course this will effect accuracy a lot in longer shoots. So, since the shafts goes to higher there should be a problem with force balance in +z, -z direction (downward & upward)....

May be when shadow is available he can give more specific approach....
 

Rat Cunning

New Member
Sep 11, 2003
28
8
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Not convinced

Hi there:

In terms of the difference in muzzle weight, I am not convinced that this could be a potential cause. The reason being that RA and RabiTech used to use the same muzzles. They now use slightly different muzzles, but the difference in weight is negligable.

A more likely candidate could be the difference in boyancy of the gunds, which differs, quite dramatically from model to model.

There is a possibility, albeit a small one, that the line release is coming into play, and that you have a shooting line that is slightly too short for both guns, but on the RA it is more pronounced because that trigger mech releases the line further on in the firing cycle. On RA and Rabitech, they release at difference points in the trigger pressure cycle.

Then there is the rubbers, the performance of rubbers can differ dramatically from rubber to rubber, as much as 30%.

However, the most likely candidate, I am afraid, to say is the individual aiming the weapon. I don't think you are conducting these tests in repeatable and structured way, so am not convinced that your gun is shooting high in the first place. You are probably suffering from a "self selection bias." So your aim is the source of the inacuraccy.

Best of luck,
 

Dogmatrix

Deeper Blues pet
Jun 4, 2002
210
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Sorry mate... I will rephrase... I don't normally shoot the gun out of the water so was thinking of boyancy as weight...
you will find the RA is "lighter" (more boyant) in the muzzle, thats about the only thing I can think of other then the handles that would effect where the guns hit...

The different handles need to be taken into account also.. as where you hold you hand in relation to the barrel may affect your shooting point also... I am only guessing at that though... I find by holding the handle firmly in the palm of the hand a miss is uncommon.

Rat Cunning many of the railguns tend to shoot slightly differently... I have mostly used edge and RA railguns... I have heard a reasonable number of people suggest the Rabbi shooting lower then the RA and no one suggesting the opposite... so I would feel it fair to say their is some substance to it... but as you say I certainly can't prove it... though again all I can think of is muzzle boyancy and perhaps handle...

Anyhow I am not a engineer... and I am sure plenty of you are... so you can tell me... I do however Know it is time for bed. Goodnight.

Rob
 
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