Posts by popgun pete

The basic advantage of this speargun design is that it combines the much more efficient energy storage of a pneumatic system with the ability to load the gun with both hands. On a normal pneumatic gun you need one hand to stabilize the muzzle while you pull on the loading handle and if needed can only employ the other hand once the spear is nearly fully inserted and the gun is no longer in danger of pivoting off your foot where the rear handle is pressing.

The big diameter piston of 500 mm squared cross-section means that internal start pressure can be relatively low while providing a high level of force for spear propulsion. As water never gets inside the gun the piston has pressure on one side and a near vacuum on the other in what is a sealed system, so it is completely unaffected by ambient pressure at depth.

Rather than the piston pushing the spear it pulls it via a cable drive using an axle in the muzzle. The only other pneumatic guns with rearward travelling pistons as they shoot are the hydropneumatic guns, but facing water braking inside the gun they require very high start pressures or multiple loading strokes to drive shooting pressure up. This makes for a lowered operating efficiency compared with standard pneumatic guns, while the Dreamair's high efficiency will only be offset by friction of the piston seals and the need to wrap and unwrap the cables and spin the pulley/drum axle. A big loading effort can be used as the spear is no longer transmitting the force to the piston during loading as like band guns loading and gun cocking are two separate tasks.

Pneumatic guns combine loading and cocking which is very efficient while the gun body and spear are short, but drops away if cocking requires several pushes to complete the charging of the gun for shooting when the gun is much longer.

To obtain a piston cross-sectional area of 500 square mm the diameter of the piston has to be slightly over 25 mm, therefore it is about double the size used in most pneumatic guns of a conventional layout. An even larger piston of double the area (1000 square mm) was used in the oval bore alloy guns which were essentially monotubes.

Another gun delivered yesterday and with it a photo showing the pumping table for this 100 cm model.

Note the long body tube for the hand pump.

Some recent photos showing gun accessories and the mounting position for a reel.

Just thought that I would add another morsel of information. Patents register new inventions which can be variations on prior ideas, but have to be different enough technically to score a patent. Registered designs protect the appearance of a product to prevent identical clones, for example in a dive mask or a speargun. Dive mask patents would have expired long ago, but registered designs are a different story. Once manufacturing went to China the whole concept of patents and registered designs went out of the window as far as they were concerned. That is why you can buy clones that only differ in the brand name shown on the item. Whether the materials used are identical is another matter, they may look the same when new, but can be made of inferior stuff. If you demand and monitor for materials A class to be used then you as an importer may get what you asked for, otherwise you may get materials Z class or anything in-between.

There is now a version of the "Dreamloader" which gives a 3:1 mechanical advantage by adding another set of pulleys on each side of the loader cables. The original "Dreamloader" with the pulleys in the wishbone hooks gives a 2:1 advantage. The loading handles need to pull three times the wishbone draw distance instead of twice the distance if you use the extra pulley sets.

Any information on the total numbers produced during this Maco2 gun's production? Guns eventually reappear when relatives sell old diver's stuff off so that over the years a trickle of guns appear in adverts. Some are seized or surrendered and destroyed if they end up in the wrong places where such guns are prohibited, but are otherwise going to endure for a long time.

The Maco2 website selection now lands on a page in Chinese with the name Daniel Wu, so it looks like the enterprise is now out of business. If you want one of these guns the second-hand market is an option. I fancy a number of Maco2 guns were sold where once the novelty wore off the gun went into storage. The Pelletier guns are very similar and at times these guns turn up on eBay. Collectors keep prices high as guns move from cupboard to cupboard when they change owners.

Well you are right, they made a mess of it as the Airbalete should have had a bulged tank at the rear near the handle and not up front behind the muzzle. They had to add air volume somewhere as otherwise the tank volume was too small. Then they made a handle out of the sort of plastic that seems to be found on most Asian sourced guns which is hard and dull with a sort of surface bloom and feels cheap (like the stuff used on plastic toys) with a tiny line release finger poking out of one side. After the initial hoopla and enhanced publicity photos the real thing was a disappointment. Then the quality which seemed a bit below par was explained by the guns coming out of Taiwan, something Omer had been keen to keep under their hat.

Bagging a Dentex

Taimen have now announced hardened stainless steel spears (Sandvik) for their guns which come in Tahitian single flopper, Tahitian single flopper with replaceable point and threaded end versions for screw on speartips with floppers. If you hunt near rocks or a stony bottom with a light sprinkling of sand then replaceable tips are recommended, otherwise you will be grinding your tips down after a shot hits the nearest available rock when it lands.

These spears have the latest screw on tails that allows replacement of the polyurethane bush which functions as a stop for the hydraulic braking slider or line slide. The polyurethane bush is backed by the "coke bottle" waisted stainless steel rear tail.

Гарпуны Таймень - Производитель ружей Таймень

Производство ружей Таймень
taimen.pro

If you have problems with the small sliding pin and its "O" rings that cross the gun's pressure boundary in order to operate the release mechanism then you can purchase this part as a sub-assembly. The item is referred to as the "Main Cork" and seems to be a better proposition than levering out the brass inserts that hold the "O" rings in place if you need to replace them as most likely the chrome plating on the pin would be damaged unless you were very careful. Of course if the plated pin is already corroded then you can replace the original part and just put it aside in case you may need it. With the guns discontinued I would advise not throwing anything away.

The 120 cm gun has now been joined by a 140 cm version seen here.

https://www.ebay.com.au/itm/PN…S-CARBON-140/133479636530

140 cm, 120 cm Carbon Max and 140 cm Corsika.

A few more photos. (taken by Stratis Gelagotis)

Note cable winding from the bottom of the drum.

Spearguns are hard to get out of Russia because they are regarded as a "weapon" which is a magic word to get the brakes applied by Customs! I guess the same applies in reverse, however having purchased a number of Russian guns it is not impossible. As you know what and where you want to hunt you really have to decide for yourself. Most guns will do the job, so it comes down to what suits you. You should be able to import a speargun as a "fishing tool" as your Customs is not overly excited by that description, and the same applies elsewhere. Any speargun, including the model suggested by Dan, can be shipped as parts, the barrel and spear in one package, the bands and handle in another, separated by a week or so in mailing. This has worked successfully many times.

Apparently the inner drum is more of a cylinder in the third version, so its contribution to gearing is fixed in the single alloy barrel model. You would still have some gearing in the beehive shaped outer drums, but the advantage is less than with spiral track drums on both. One needs to remember that the shot is the loading effort replayed in reverse, hence provided you can cock the gun it does not really matter. On a standard pneumatic the compression ratio is about 1.10, so the force at latch is 10% greater. Might not sound much, but with pneumatic guns that are pumped right up that extra 10% can be an eye-popping effort with your arm in a position where you cannot apply much more grunt. If the gun had a constant pressure then loading would be easier, but that would require a massive air reservoir allowing the gun to have a compression ratio of 1.0. Now with the Dreamair you can offset that 10%, or part of it, by the gearing system offered by the spiral drums. That means you have a chance of loading it at higher pressures, so any gearing helps. In fact you really need it as the compression ratio is about 1.50, which is 50% more effort at latch.

The downside, if say you are comparing it to a multiple band gun, is that in effect you are loading all the bands at once, there is no splitting of the loading effort. That is why for higher pressure you need the Dreamloader, which stages your effort rather than splits it. Compressed air is a lot more efficient at energy storage than rubber bands, but losses in the drum and sliding piston system are unknown, although they should be low with some energy being required to spin the drums and axle.

The “Dreamair” is a big piston gun which would not be practical in a standard pneumatic gun layout with a wet barrel, but provides higher force levels thanks to that larger cross-sectional area facing the gun’s internal air pressure.

In this next video the alloy internal barrel gun is shown in action, note the changing graph displayed on the left hand side of the screen as shots are taken at different ranges.

https://youtu.be/E9-hmkNtW6Y

Another video. In this video we see the gun floating after the shot, tail down due to the reel. All carbon version of the "Dreamair".

Dentex Passion

Moment of hit.

Inner cable sweeps the interior as the inner drum winds in the piston, as shown in the sketch. The bore size of the barrel determines whether it has a free path without touching anything as it traverses the surface of the drum. The gun will be longer than the sketch image shows, but gives a general idea of how it needs to work.

Another view of the gun and the hand pump for pressurizing it at the start of the season.

New single barrel alloy gun in a carbon fiber hull.