AQUATECH Black Sea User manual

Aquatech "Black Sea" Speargun Operating Instructions
October 2009 edition
Initial Preparation of "Black Sea" Speargun Prior to Charging
Enter the water with the spear removed from the gun and the automatic line release lever swung out to the open
position after pulling the plastic trigger to release it. With the gun totally submerged, or at least completely
submerged at the rear end, operate the hydropump lever to flood both the hydropump's narrow tubular body and the
gun's internal "hydraulic locking chamber"; five or six full strokes of the hydropump lever should be sufficient.
Next flood the speargun's inner barrel with water, if it has not already been flooded, by submerging the muzzle.
Then insert the spear into the muzzle and push it down into the inner barrel until it reaches the end of its travel. Very
little effort will be required as the water injected during this process will be exiting through the already open
"trigger control valve". Note that the position of the line release indicates the status of the "trigger control
valve"; when the line release is open the "trigger control valve" is open, when the line release is closed the
"trigger control valve" is closed.
Now with the gun fully submerged pull the spear partially out of the inner barrel to about the half-way position and
then push it back in again. This action pumps additional water through the gun's inner barrel eliminating any
remaining air bubbles in the barrel and "hydraulic locking chamber" as the sliding "O" ring spear tail relief valve
motion will allow more water to pass into the inner barrel from outside the gun when the spear is pulled forwards.
Repeat this spear pumping action once or twice to ensure the gun's hydraulic system is completely flooded and then
push the spear down to the fully inserted position. Note that a completely flooded hydraulic system is essential to
the gun's shooting performance, so all air bubbles should be completely purged from the "hydraulic locking
chamber".
Next swing the line release lever back to the closed position, this resets the trigger and closes the "trigger control
valve", you will hear the trigger click into position as it engages the slot in the rear of the line release lever. Closing
the "trigger control valve" completely seals off the "hydraulic locking chamber" which is the basis of the gun's
relatively silent shooting operation compared to that of other pneumatic spearguns. Now arrange the shooting line on
the front line hook at the muzzle and the line release lever at the handle in a series of line wraps so that the shooting
line is neatly stowed on the "Black Sea" gun. The gun is now ready for charging by working the hydropump lever.
Note that the line release must be in the closed position in order to charge the gun for shooting.
Charging the "Black Sea" Speargun for Shooting
Support the rear of the gun (while rolled onto its left hand side) against the right knee while holding the gun
horizontally across your body, one hand holding the forward barrel section of the gun while the other hand grasps
the front end of the hydropump lever. Adopting a slightly upright sitting position while floating at the water's
surface makes the gun hydropumping operation easier. With the gun fully submerged opening the hydropump lever
outwards injects water into the gun (hydropump power stroke) while closing the hydropump lever back against the
gun body (hydropump return stroke) sucks more water from the surroundings into the hydropump's tubular body.
Maximum shooting power requires a full set of hydropump lever strokes that have the combined effect of injecting a
cumulative volume of water equivalent to the inner barrel's internal volume. If necessary rest breaks can be taken
both between and during successive hydropump lever strokes as the hydropump system has a "non-return valve" to
stop injected water coming back out of the gun again. Lower power shots can be achieved by using less hydropump
lever strokes per shot, however water must then enter the inner barrel through the "spear tail relief valve" once the
compressed air driven internal water column ceases pushing the spear from the gun. Water flowing backwards
through the "spear tail relief valve" minimises the suction effect developing behind the departing spear tail.
Basically the shorter propulsion distance for the spear in the inner barrel produces the lower power shot. The
momentum achieved by the spear up until the moment that the water column behind it ceases pushing the spear is
what allows the spear to exit the inner barrel, although at a reduced velocity.
To gain full performance from the "Black Sea" gun and the maximum spear velocity use the full number of
hydropump lever strokes indicated for your model of the "Black Sea" gun. Longer barrelled "Black Sea" guns will
require more hydropump lever strokes as a longer column of water is required to propel the spear under power for
the entire length of the inner barrel, hence the maximum number of strokes needed is dependent on the gun's inner
barrel length.
Cleaning the "Black Sea" Speargun after completion of the Dive
At the completion of spearfishing it is recommended that you purge any remaining saltwater from inside the gun.
There is always some saltwater trapped inside the "hydraulic locking chamber" after the gun has been used for
spearfishing in the ocean. The trapped saltwater can be easily replaced with freshwater without dismantling the gun
and by doing so you will minimise the possibility of internal corrosion occurring until you have the opportunity to
open the gun at the rear end for more thorough cleaning at a later time. The procedure used is identical to the
flooding of the gun described earlier, except that the rear of the gun should be submerged in a tub of freshwater so

that the hydropump body is covered and can readily take in water when the hydropump lever is operated. Make sure
that the line release lever and therefore the "trigger control valve" is open and lift the gun clear of the water each
time that you open the hydropump lever outwards. This is normally the hydropump power stroke, but with the
"trigger control valve" open you will see water exiting from around the trigger area each time that you do this as
water is being pumped right through the gun's internal hydraulic passages, including the "hydraulic locking
chamber". Closing the hydropump lever should be carried out while the rear end of the gun is submerged in order to
allow the hydropump to suck in freshwater on each return stroke of the lever. If the tub of water is not large enough
to allow the full swing of the hydropump lever when the gun is in the tub then close the hydropump lever against the
gun body with it out of the tub and then submerge the rear end of the gun in the tub while holding the "Black Sea"
gun as close to vertical as possible. The water level in the tub should be at least deep enough to cover the ring of
hydropump breather holes in the mid-section of the hydropump body. Water will then flow downwards into the
hydropump body under the influence of gravity, watch for tell-tale air bubbles emerging as the hydropump's tubular
body fills with water. Then continue pumping freshwater through the gun as before, but you need to keep the gun
close to vertical when it is first raised from the tub, but once the hydropump plunger starts to push on the water
inside the hydropump body then you can safely incline the gun as the water will no longer be able to run out of the
entrance to the hydropump. Four or five complete hydropump lever strokes should be sufficient to clear all the
saltwater from the rear end of the "hydraulic locking chamber" and the connecting passages and tubular body of
the hydropump as well as the "trigger control valve" through which the water ultimately exits the interior of the
gun.
Next fill the inner barrel of the gun with freshwater from a small container like a jug or bottle while holding the gun
vertically with the muzzle pointed upwards and then insert the spear tail into the inner barrel. Note that the line
release and hence the "trigger control valve" must always remain open throughout this cleaning procedure. Push the
spear down by hand into the gun and the water in the inner barrel will be driven through the "trigger firing valve"
as it opens, the water then moving through the "hydraulic locking chamber" and flowing out of the open "trigger
control valve". There should be no significant pushing effort involved in performing this task, the spear will be very
easy to move by hand down into the inner barrel. Remove the spear, refill the barrel with additional freshwater and
repeat the insertion of the spear into the gun, then remove the spear and place it to one side. The gun will now be
completely free of saltwater throughout all its internal spaces, however the "hydraulic locking chamber" will be
filled with freshwater instead.
You can leave the line release lever in the open position when storing the gun between dives, the line release lever is
only closed when the gun is being charged for shooting the spear or you wish to carry out a "dummy shot" without
the spear in the gun. Water shot from the gun is ejected with considerable force during a "dummy shot", do not use
the gun as a toy water pistol or point it at any person, even without the spear inserted.
Firing the spear from the gun when not submerged is absolutely forbidden as the spear will travel great
distances in air with potentially lethal consequences from both gun recoil and strike of the spear.
Preparation for Long Term Storage of "Black Sea" Speargun: Partial Disassembly
If you wish to fully dry out the "Black Sea" gun for an extended period of storage then undo the small screw of the
stainless steel collar that holds the plastic anchor piece for the front end of the hydropump body and then pull the
collar away from the slotted nose end of the hydropump's body tube. The rear of the hydropump's tubular body can
be pulled off the stainless steel elbow fitting by wiggling it very carefully, it is only a tight press fit on the end of this
fitting. (Note that for the later rear handle models with the hydropump and the handgrip assembly mounted
together in a removable rear housing the next couple of steps can be omitted as both the grip handle,
hydropump and hydropump lever system unscrew from the rear end of the gun as one single unit. That
means that the hydropump body can be left attached to the rear handle section if you wish.) Swing the now
detached hydropump body and metal connecting levers away from the gun and pull the hydropump's narrow tubular
body from the hydropump rod plunger that is the pumping element. It will now be possible to unscrew the rear
stainless steel tail cap with the elbow fitting and the attached levers as a single unit from the rear of the gun. (The
screw threaded rear tail cap is an integral component of the removable rear housing for the later rear handle
models.) This action will then expose the long internal coil spring (biasing coil spring) with the rubber valve seal on
its rear end that serves as the "non-return valve" for the hydropump. Remove this coil spring from the rear of the
gun. If you wish you can also remove the "trigger firing valve" (this is highly recommended) by putting some water
in the inner barrel and inserting the spear as before. A slight push on the spear will eject the "trigger firing valve"
from its position at the front end of the "hydraulic locking chamber" and out the rear end of the gun along with all
the water that was previously poured down the barrel, hence arrange for someone to catch the "trigger firing valve"
or have it fall into a suitable container positioned under the rear of the gun which will also collect the water coming
out.
The gun's inner barrel will now be completely open from one end to the other, you can now squirt freshwater from a
garden hose right through the gun body if you wish. The gun can be stored with the disassembled parts in different
locations in your home for security reasons as without the "trigger firing valve" and the biasing coil spring which
is located immediately behind it the "Black Sea" gun is incapable of being operated.

Reassembly of the "Black Sea" Speargun
Reassembly is the reverse of dismantling, use only a drop of light oil on the "trigger firing valve" body "O" ring
and the rear of the coil spring to lubricate the rubber disc of the hydropump's "non-return valve" to facilitate their
assembly and preserve the rubber surfaces as the stainless steel hydropump tail cap is screwed back into place. Note:
A few small drops of light oil are all that is required, do not over lubricate these parts! The main body "O" ring
and screw threads at the rear end of the gun should also be lubricated with some oil before reassembly, again only a
few small drops are required. Also use some of the same oil on the hydropump body tube's front and rear "O" rings
when refitting this item. It is not recommended that you use any type of grease, a very light oil of SAE 10 grade
should be sufficient, the same type of oil as used inside pneumatic spearguns. During diving use seawater or lake or
river water provides the necessary lubricant for the internal moving parts, the light oil used during the re-assembly
work will soon float off the internal surfaces after a few shots with the gun.
Grease or similar thick, sticky substances can cause sand particles to adhere to internal parts which are undesirable
in a gun where there are many precision machined internal surfaces.
Operational Considerations when using the "Black Sea" Speargun
As a general rule try to keep sand out of your gun by avoiding the dropping of the gun in sandy bottom locations as
it is undesirable to have sand particles enter the hydropump due to its small internal passages, plus sharp sand
particles have the ability to scratch smooth internal surfaces, particularly if they are quartz-type grit materials. If you
do happen to drop the gun in a sandy location underwater then retrieve the gun and hold it vertically with the muzzle
pointed downwards and give it a few vigorous up and down shakes while the gun is still fully submerged, this
shaking action will cause any sand grains to fall out of the hydropump entrance and the inner barrel under the
influence of gravity. Sand will be unlikely to have penetrated the "hydraulic locking chamber" under these
circumstances as it is closed at either end by the two valves. Executing a subsequent "dummy shot" will help blow
any ingested particles out of the gun. If in doubt, or the motion of the gun's moving parts feels or sounds gritty,
disassemble the gun at the first opportunity to both inspect it and clear the internal passages of any sand grains or
other foreign particles.
Taking good care of your gun will be rewarded by years of trouble-free service, especially as the "Black Sea" gun
is one of the most powerful spearguns ever made and requires some respect in terms of its operation, handling and
post-dive maintenance. The powerful and long shots of this gun require extra care when operating it near other
divers, make sure of your target before touching the trigger to avoid any accidents. Keep a firm grip on the gun
when firing it in order to control the recoil, particularly when the gun is charged up for maximum shooting power.
Make sure that the shooting line is properly rigged before shooting the gun, especially when using full power as the
line will be pulled very strongly from the gun.
Warning: The "Black Sea" gun is a professional hunting tool and not a toy; it should not be handled by
anyone who does not fully understand its operation before attempting to use it. Keep the gun away from
children and do not leave it unattended where people may play with it who have no idea of the extremely high
air pressure that it contains. Also keep the gun as cool as possible, do not leave it for long periods under a hot
sun without covering it up or inside a parked vehicle with the windows fully wound up as interior
temperatures can reach very high levels in vehicles under such circumstances during the summer period.
Schematic diagram parts reference:
1 –rear tail cap; 2 –biasing coil spring; 3, 5, 6, 15, 26 –sealing "O" rings; 4 –trigger firing valve; 7 –spear tail; 8
–compression chamber; 9 –air release screw; 10 –spear; 11 –barrel; 12 –slide ring; 13 –plastic guide; 14 –spear
tip; 16 –rear threaded boss; 17 –hydropump non-return valve seal; 18 –transfer channel; 19 –annular piston; 22 –
plastic trigger; 23 –valve/nipple; 24 –hydropump lever; 25 –hydropump body; 27 –hydropump breather holes;
28 –hydropump rod plunger.
The biasing coil spring is located inside the hydraulic locking chamber, the spear tail relief valve is "O" ring 6.