Russian "Argument" pneumatic speargun

[cebru]

Hi,

I discovered the forum and its incredible resources including pneumatic guns. Every reading was of great interest.
I am looking for a pneumatic speargun with a small diameter (less than 30mm). I read with great interest Popgun Pete posts about the gun Taimen http://forums.deeperblue.com/threads/taimen-russian-pneumovacuum-speargun.82933/.

I wanted to know if some of you know this one : http://www.fishgun.spb.ru/index.php?page_id=hanter&item=argument&r=photo

According to the fact that my only experience with a pneumatic gun is limited to a few hunts with a Mares Cyrano I wonder about the reliability of this particular weapon.

The rifle is available in a length of 60cm and without power reducer and security.
I would like a longer 1m or 90 cm and with a safety and reducing power weapon.

Knowing that the gun is made by hand do you think that such modifications are honestly feasible and of interest.

If some of you know this rifle, or its creator thanks for the help you could give me.

Take care.

 

[popgun pete]

More about it here: http://www.fishgun.spb.ru/index.php?page_id=samopal&item=argument_riga

 

[popgun pete]

This looks to be an interesting lightweight (when made of alloy, not titanium!) pneumatic speargun that has a roller type "sear tooth" that locks on the front step of the window cut into the rear end of the inner barrel. The brass collar (sear block) is pulled forwards by the trigger operated pull rod to release the roller as the angled face on the piston's mushroom head can then drive the roller downwards when there is nothing positioned underneath the roller (refer annotated version of components diagram). What I have termed the "main body "O" ring" may be the "return spring" on the roller sear, but it is hard to tell from the photos.

It would be difficult to use a partitioned reservoir power regulator system in such a small gun, so the simplest power control option would be a throttle type, but the window into the inner barrel is part of the trigger mechanism (with that square cut front step), hence not much scope to close off the window and shut off the air flow. To achieve a noticeable power change a low power port needs to be very small, yet the window is quite large and parts move fore and aft within it.

As for a safety device: a lever "A" could be swung up behind the trigger which would normally be hidden in the handle, or a lever "B" could be hidden in the trigger finger guard frame like the one used on the Technisub "Grinta" and the "Drago". If you are disciplined and methodical you don't need a safety device, but it is handy to have one when wrapping the shooting line as that is when you have less control over the gun as your focus in on the line wrapping task. For legal purposes a safety is good to have, just as removing one will create a difficult situation when explaining this action in a court if an "unfortunate event" does occur.

 

[tromic]

This gun has hydro shock absorber and it is water barrel pneumatic speargun.

 

[popgun pete]

One thing that I cannot see is the air inlet valve, it should be in the rear bulkhead, but the bulkheads have no opening in some of these photos where I would expect to see the connection for the hand pump. Also is the "return spring" on the "sear tooth" cylinder really a rubber band? If it is then what will be its service life?

 

[tromic]

One thing that I cannot see is the air inlet valve, it should be in the rear bulkhead, but the bulkheads have no opening in some of these photos where I would expect to see the connection for the hand pump. Also is the "return spring" on the "sear tooth" cylinder really a rubber band? If it is then what will be its service life?

As I remember, pumping is accomplished using the piston (smaller OD O-ring) and the spear.

 

[popgun pete]

As I remember, pumping is accomplished using the piston (smaller OD O-ring) and the spear.

Where is the inlet valve function?

I can now answer my own question as I found this schematic diagram on a separate web-page. The valve function is split between the piston and the line release pin that pokes out the rear end of the gun.

 

[tromic]

Here is more info:
http://podvoh.net/forum/ruzhya/141885-ruzhya-argument.html?limitstart=0

Inlet valve function is the smaller O-ring (red arrow).

 

[popgun pete]

The second photo explains the pumping action, so the piston bearing the inlet valve has to be locked into the sear before you start pumping with the spear shaft and this extra pumping piston added to its "inner" end (as in its use here). You would not want the "sear tooth" roller to let go of the barrel sliding piston while performing this pumping task!

 

[popgun pete]

Although intriguing to have the gun pressurized in this way it would be far simpler to connect a hand pump into the rear end of the gun as was done with the clone of the "Argument" shown on Hanter's web-site and referenced above, although I did not realize that gun was a clone when I first saw it (a conventional hand pump connection is used on that gun).

More web pages on the "Argument" speargun that describe both its operation and maintenance are here:
http://www.fishgun.spb.ru/index.php?page_id=hanter&item=argument&r=instruction&sub_r=razborka
http://www.fishgun.spb.ru/index.php?page_id=hanter&item=argument&r=instruktion

I have manipulated the gun's schematic diagram to show how the trigger mechanism operates. The rubber band return spring is not shown, but this band wraps on the roller "sear tooth" by the band's loop ends being held in place by the larger end pieces on the roller. The roller (15) is hardened to stop it bending, being a needle bearing component, as is the pin (17) that fastens the rear bulkhead. Compressed air pressure inside the gun biases the trigger "push rod", although as the rod does a U-turn inside the gun it is also a "pull rod" as far as the sear block is concerned, so no need for a spring on the rod.

 

[tromic]

Nice, Pete!

 

[popgun pete]

I think if anyone wants a small diameter reservoir gun with the handle set in the middle, or slightly further back, then this "Argument" gun is both small and floats after the shot, so it would be a good choice. If you want the handle at the rear and a power regulator then the "Taimen" seems to be the best option, based on the guns reviewed here to date as it has been fully sorted out and is a floater. However a metre long gun does not really need to be a small diameter reservoir gun, but ultimately it depends on where and what you hunt. Open water or a heavily vegetated environment which presents obstructions and tangles will also have a bearing on the gun selected, even if the underwater visibility in the latter situation is relatively good.

 

[cebru]

Pete,

Thank you so much for taking the time to answer me with so much detail. I understood almost all despite the quality of my English, your explanations are very clear and it made me very happy. I find the ideas for the safety device very simple and very ingenius in fact.

I hunt since the age of 16 years, mainly in the Atlantic Ocean near the coast. The shore is very exposed to swell and I realized my shots more often in shallow water (between 3 and 10 m) fishing in the surf and very close to the rock ("indian way" hunting) or on the rock ; sometimes holes in the rock.

I want a gun for to get the fish up to 3; 4m max (from the point of a gun). I currently use a wooden gun (single or double bungee) with a total length of 1.15m. I am very satisfied with the accuracy and ease of use but the movements of the weapon in a high or average swell are difficult.

What appeals to me in this type of pneumatic gun (argument or taimen) is its small diameter. With lengths of 90 cm or 100 cm I hope to find the ideal weapon combining range and ease of movement.

The power regulator is essential for me. From what I understood the speargun Argument will not allow it even if I ask for it with its designer (builder). Is that right?

I was ready to order me Taimen when I discovered the gun "Argument". What I liked was the ability to shake the handle of the gun by closing my index above it without touching the trigger. This makes the handling of the weapon very strong and really facilitates its movement.

I do not see how it would be possible to modify the Taimen to move the trigger forward to accommodate my right index finger behind (between the trigger and the butt). If someone have any Idea ....


I will read in detail the various links ... and I would probably still have some questions...

Thank you again.
Take Care

 

[popgun pete]

Maybe consider the universal handle for the "Taimen" as it is less bulky to get your hand around. I don't have one, but have been thinking about ordering one for my gun. The changes are more than just the absence of the thumb support ridge on the LHS of the grip as the girth of the grip is now less and the trigger finger guard opening is larger.

As I indicated in my "Taimen" shooting and handling report the old "Taimen" handle has my fingers squirming around trying to improve my grip when I am not thinking about actually shooting something. The problem is the downwards sweep of the outwards curving ramp below the thumb support ridge stops the distal phalanges of my ring and small fingers from easily fully pressing down onto the lower grip handle's lateral faces as the tips of those fingers are held at a slight angle outwards on that curving slope or ramp. This lower handle shape limits the ability to fully tighten my grip on the handle for long periods of time, so you slacken your hold on the gun for most of the time and hence your fingers start searching for a tighter hold when you start thinking about it again. Once you line up on a potential victim you tighten your grip and the gun firms up in your hand as you pull the trigger, but you cannot swim around with the gun like that and I guess you don't have to as you will not be in danger of dropping the gun in any case. The slightly offset to the right shots were when I casually fired at distant bits on weed on the sandy bottom, I had not tightened my handgrip as I would with a potential victim being lined up and hence the gun's handle turned ever so slightly in my not full clamping pressure handgrip. The "universal" handle gets rid of that lower ramp, so those two lower fingers will now be able to hold the handle more firmly with less conscious effort.

 

[popgun pete]

Here is why the sear tooth in the "Argument" speargun is a roller, the piston tail has to push the roller backwards and downwards before the roller lifts back up again and engages on the other side of the piston tail to hold onto it. The lifting action is provided by the rubber band loop biasing or return "spring" (not shown on the diagram).