"Mavka" pistonless speargun prototypes

[popgun pete]

On the “Vlanik” pistonless gun thread there was an image of two guns that looked very attractive and a search has discovered them on the www.akvalang.com website. The top gun is a 70 cm model and the lower gun is a 55 cm model. The 70 cm gun has a side-mounted line release while the 50 cm gun has a passive magnetic clip similar to the Pelengas release lever.
https://forums.deeperblue.com/threads/vlanikgun.90450/page-5

https://www.akvalang.com/forum/topic/11348-mavka-besporshnevoe-ruzhe/

Roman (Adept6) has described the guns there, but unless you are a member you cannot see the photos and so I am reposting some of them here. The guns were created by Roman who also did the “Arma” speargun, hence the similarity in the style of the grip handles. https://forums.deeperblue.com/threads/russian-arma-pneumatic-speargun.102782/#post-959969

Here are photos of the muzzle and spears used with the guns.

The grip handle and barrel which has an integral shroud incorporated for buoyancy on a 22 mm diameter tank tube. Note that the trigger pivot pin is in the lower trigger finger guard frame.

The plastic trigger operates the sear lever arm in the muzzle, which is basically a single piece trigger, via a slim pull rod that runs under the tank tube to the muzzle. Note the step in the front of the spears for the sear tooth (which is of a cam type) to engage rather than an annular notch.

 

[popgun pete]

One big feature of these pistonless guns is the working course of the piston is maximized as basically the gun barrel is a long tube that serves as the pressure tank, there being no inner barrel and no works inside the gun as everything happens at the muzzle. A disadvantage, bar requiring higher internal pressures as the spear diameter is small and is in a sense its own inner barrel, is the presence of annular notches in the spear shafts that can weaken them at the front end. One way around this problem is to put a raised section or short collar on the shaft for the forward latching sear lever to engage instead. The forward latching spearguns need to use front tied shooting lines which can effect accuracy, but it depends on how the shooting line streams along beside the shaft during the latter’s flight to the target.

 

[popgun pete]

More information on the "Mavka" pistonless speargun can be found here.
http://garpun.spb.ru/forum/viewtopic.php?t=1147
The 70 cm "Mavka" gun with reel fitted (Pelengas)

"Mavka" trigger pull rod, bifurcated sear lever arm, trigger biasing spring and sear which is the cylindrical element with the cutout that releases the spear when rotated by pulling the trigger.

This combined photo shows how the biasing spring is fitted onto the trigger pull rod.

 

[popgun pete]

Muzzle details including line wrapping detail of muzzle front line hook. Image below shows inverted muzzle with detail of trigger pull rod connection to swinging sear lever arm which functions as a single piece trigger. Note the biasing spring which pushes the sear lever arm forwards after you have pulled and then released the trigger. From the comments on the Russian and Ukrainian forums it seems that you can insert the spear into the "Makva" gun without having to pull the trigger, something that often needs to be done on forward latching guns to ease the spear tail past the sear tooth.

Line wraps on front line hook in lateral view of "Mavka" muzzle nose.

Line wraps on cocked ready to shoot "Mavka" pistonless gun, note that the gun is shown inverted here.

 

[popgun pete]

Pistonless guns have the potential to swallow water, maybe only a tiny amount, if the water in the front cavity of the spear tail cap after the shot is not completely squeezed out when the tang of the shaft is pushed into it during reloading of the spear shaft. Properly machined the spear tail cap will butt smoothly with the shaft body so that the join in the shaft that passes through the muzzle seal will not break the seal or have any water inside the almost microscopic gap, but there may be some water in the cavity as butting two surfaces with absolutely no gaps is very difficult both internally and externally, it will usually be one or the other. If the water is in the tail cap cavity then it is important that it stays there and that the cap does not fall off inside the gun.

 

[popgun pete]

This diagram shows how the "Mavka" gun works if you study it closely.

 

[Vlanik]

Нарисовано красиво, но повторять так нельзя...

 

[popgun pete]

[QUOTE = "Vlanik, post: 982179, member: 19907"] It is drawn beautifully, but you cannot repeat it like this ... [/ QUOTE]
No one will be making such a pistonless speargun here in the West as too much already invested in relatively low pressure (20 atm to 30 atm) pneumatic spearguns with 11 mm to 14 mm diameter pistons. Even high power hydropneumatic guns with 100 atm to 200 atm start pressure produce little interest, plus spare parts availability is everything. Something like new "Mavka' gun may be of interest, but requires high quality surface finish spears. Until pneumovacuum guns arrived here with the “Mamba” speargun and the “Mamba” muzzle conversion kits the pneumatic gun spears were usually spring steel and either zinc or cadmium plated, but often developed a rusty surface which was of no real concern as the spear slid through nothing but the line slide and the fish. Only relatively recently have spears switched to precipitation hardened spring stainless steel, but by no means all of them as there are many “bread and butter” model spearguns still sold with silvery plated spears which are mainly plated to look good in the shop..

At least with the pistonless spearguns there are so few parts that there is little to go wrong, but any annular notch may pose problems with strong fighting fish acting on the shaft and although not common guns are in use up to 140 cm, and in the case of Mares “Supersten” even longer, up to 150 cm. As for the “Mavka” diagram it is already widely dispersed around many spearfishing forums on the Web.

 

[Vlanik]

Мавка делалась под моей прямой консультацией...И она выполнена не так как ты нарисовал... Ты выкладываешь тут красивые картинки...Так выложи и работу этих картинок в реальных условиях...Уже более 15 лет, идут попытки создать беспоршневое ружьё превосходящее ружьё Vlanik...Но получаются недоразвитые выкидыши...А обладателей реальных ружей Vlanik несколько сотен человек...И эти ружья реально работают по рыбе в самых суровых условиях... https://www.instagram.com/vlanik_gun/

 

[Vlanik]

Название темы не соответствует действительности...Мавка, это беспоршневое ружьё...

 

[popgun pete]

[QUOTE = "Vlanik, post: 982188, member: 19907"] The topic name is not true ... Mavka, this is a pistonless pistol ... [/ QUOTE]
The title is "Mavka" pistonless speargun prototypes

Do not be misled by translator error as often "not" is read "as is" and vice versa, "Не" (not) often ignored or confused as grammar is different. I fully understand your gun and this one as I studied all Russian and Ukrainian guns since my association with Sergiy Kravchenko began in 2000 when there was no auto-translation facility and I had to use a well-thumbed Russian to English dictionary. First translation job RPB-1M passport or handbook for operating,

Your guns in 2004 were like this one which we discussed at the time, this gun not being a floater after the shot.

Possibility of tail cap falling off gave rise to "turbine piston" suggestion and that is when I first contacted you. You will receive respect here, but respect is a two-way street, so do not take any of us for fools.

This idea would not work as a dual power gun as difference between volumes is not great enough, but primary aim was to provide tail cap with tunnel to travel in by providing thin wall skating barrel for turbine fins. Since that time you stabilized tall cap with rear bulkhead shape which is also repeated in “Mavka” gun.

 

[Vlanik]

Я ещё раз повторяю, что ты нарисовал Мавку не правильно...Потому что мавка это клон Вланика и конструктивно выполнена по чертежам Вланика... При полной консультации со мной...

 

[popgun pete]

Various sear to retention notch contacts are explored here for pistonless guns.

 

[popgun pete]

You can see from the previous diagram that a 3 ball sear arrangement only has three line contacts shown in blue due to the curvature of the balls and the groove in the shaft, provided the curves match. A dropping sear tooth has the greatest contact area as the flat rear face of the tooth can engage the flat face of the spear tail notch immediately behind it. The third version uses a transverse cylinder with a curved notch machined in it to allow the shaft through once the cylinder is rotated to allow the alignment of the notch to pass the shaft through the cylinder. The contact here is virtually a point contact unless the face of the shaft notch is curved to match the curve of the cylinder, however this sear arrangement has been used for decades and goes right back to the John Salle pneumatic speargun where it held the rear of the barrel sliding piston. Many forward latching spearguns use this arrangement rather than the miniature two-piece trigger mechanism borrowed from spring guns such as is used in the “Kobra” and “Triton” forward latching spearguns. Another gun that uses this trigger mechanism is the Soviet-era RPB-1M which was sold as the "Prizm" for a time in the West via Klondike Imports. The "Prizm" diagram is shown below the "Kobra" diagram.

 

[popgun pete]

Alpinasub now offer a pistonless gun based on existing components, but suitably modified. Maybe a better proposition than begging and cajoling Vlanik to sell one of his guns. New gun is RPP-5EX. i assume "EX" means no piston. (Well now I know that it does not, see later).

 

[Vlanik]

[QUOTE = "popgun pete, post: 982422, участник: 18674"] Alpinasub теперь предлагает поршневое оружие на основе различных компонентов, но соответствующим образом обновленным. Возможно, лучшее предложение, чем попрошайничество и соблазнение Вланика продать одно из его орудий. Новое оружие - RPP-5EX. Я предполагаю, что «EX» означает отсутствие поршня.
[/ QUOTE]
Ты ошибаешся ... Это поршневое ружьё ... К ружью Вланик, не имеет никакого отношения.

 

[popgun pete]

[QUOTE = "Vlanik, post: 982424, member: 19907"] [QUOTE = "popgun pete, post: 982422, member: 18674"] Alpinasub now offers piston weapons based on various components, but appropriately updated. Perhaps a better offer than begging and seducing Vlanik to sell one of his guns. New weapon - RPP-5EX. I assume that "EX" means no piston.
[/ QUOTE]
You're wrong ... It's a piston gun ... Vlanik has a gun, has nothing to do. [/ QUOTE]
Information sent to me personally from Alpinasub earlier today.
"More recently released speargun RPP-5, which with a piston, but as a pistonless. The reliable eccentric hook is used. Photos in the attached files."

 

[popgun pete]

Совсем недавно выпускали арбалет RPP-5, которые с поршнем, но как беспоршневые. Используется надежный эксцентриковый крюк. Фотографии в прикрепленных файлах.

For those who do not understand Russian, "беспоршневые" means without (бес) piston (Поршня).. Endings of words change to reflect the grammar, the words mean the same thing, similar to Latin. For example pistons is Поршни in Russian. Without pistons is без поршней.

Alpinasub need to give this pistonless version of their gun a new name as otherwise confusion will reign. The "EX" suffix is on the piston version as well, so from the outside the only clue will be the spear tail machined down at the rear end for the detachable spear tail cap. I would expect no muzzle relief ports, but the muzzle seal may be rearward of them as it is on the “Kobra". The "Ex" seems to be the "eccentric hook" sear lever, which is a cylinder with a cutout on one side that revolves into a position where the spear releases.

The RPPA gun is in essence an update of the "Prizm" RPB-1 M , but with a plastic molded grip handle instead of the cast alloy version. The sear lever is of the pull down sear type which is linked to the trigger.

 

[popgun pete]

I would think that the "Kobra", which is a sealed muzzle hydropneumatic gun somewhat similar to the RPS-3, could be transformed into a pistonless gun with the inner barrel removed, as long as the inner barrel does not hold the gun together. If it does then front and rear bulkheads must be screw attached to the tank, which is really requiring a new gun and possibly a thicker wall tank tube to take the machining of the necessary screw threads. The muzzle would need a recess and impact absorber to catch the detachable spear tail cap.

 

[Vlanik]

[QUOTE = "popgun pete, post: 982427, member: 18674"] Я бы подумал, что "Кобра", представляющая собой гидропневматический пистолет с запечатанной мордой, чем-то похожий на RPS-3, может быть преобразована в безпоршневой пистолет с внутренним ствол снимается, пока внутренний ствол не удерживает пистолет вместе. Если это произойдет, то передняя и задняя переборки должны быть прикреплены винтами к резервуару, что действительно требует нового пистолета и, возможно, более толстой стенки резервуара для обработки необходимых винтовых резьб. Морде понадобится углубление и ударопоглотитель, чтобы поймать съемный наконечник копья. [/ QUOTE]
Ну а почему бы тебе не воплотить свою идею в жизнь...Хотя подобных прожектов уже множество, а рабочего ружья нет...