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Pneumatic dismantling: how to get inside

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Sometimes a pneumatic speargun will be difficult to disassemble easily because the parts are a tight fit (like in a Mares "Mirage"!). I have found this method useful on most rear handle pneumatic models.

First release all the air with any power selector set to "maximum" as this ensures that all the air chambers in the gun are connected to each other, that way you will not leave any compressed air inside the gun. Then take the spear or a blunt ended rod of similar diameter and push the piston back so that it just disappears into the inner barrel and leaves a clear view through the muzzle's relief ports. Using a metal rod, or a screwdriver that is a reasonably close fit in the relief ports, pass it through opposing relief ports to provide a handle whereby you can unscrew the muzzle by hanging onto each end of the rod or screwdriver (round shaft Phillips head type, not a blade tip screwdriver). Sitting down on a chair you can trap the grip handle between your feet as you apply a twisting torque to undo the muzzle while holding the gun vertical between your knees. Generally the muzzle will come off easily after only a few turns, so you can unscrew it the rest of the way with your fingers. Put some fresh grease on the exposed muzzle threads and then screw the muzzle back on. When the muzzle contacts the nose cone, you will feel the muzzle stop turning, back the muzzle off a number of turns to leave a gap. Now take the gun's handpump and screw it into the rear of the gun. With the muzzle pointed downwards and resting on a rubber surface like an old thong (the "flip-flop" footwear type) begin pumping using slow strokes and watch the muzzle nose cone. A small amount of air pressure in the gun will cause the nose cone to slide down the inner barrel tube and out of the tank, the reason that you only unscrewed the muzzle by three or four turns was to make sure that the nose cone did not come right out of the tank or you would have oil everywhere, plus you want the piston to stay in the inner barrel bore without the piston seals emerging for the exact same reason.

Now remove the handpump and release any air from the gun as before, there will be very little pressure with only a small number of pump strokes. Unscrew the muzzle and remove it, then twist and pull the nose cone and slide it up over the inner barrel threads. You will find that the "O" ring on the inner barrel tube has chased the nose cone part way up the inner barrel threads, that is why you greased them earlier. Make sure that the nose cone has its outer "O" ring, sometimes it falls off and will be inside the tank, in which case you will need to retrieve it later. Pull the piston out of the inner barrel and up end the gun over a clean container like a glass screw top pickle jar to collect the oil. Leave it for a while to fully drain the oil out of the gun, then return the gun to the barrel up position and screw the muzzle back on to about half distance on the screw threads. Now hold the gun by the front of the tank in one hand and strike the muzzle nose with a soft faced hammer (preferably a nylon faced, double sided hammer like a "Thor", that is what I use). A few good hits and the barrel and handle will drop out of the tank tube, make sure that it does not have too far to fall and then the rear of the muzzle will not hit the front end of the tank. I hold the gun just clear of the floor with a rubber thong directly underneath the grip for the back of the handle to fall down onto, that way there will be no damage to anything. Unscrew the muzzle, put it to one side and carefully lift the tank clear of the inner barrel and place the tank on a level table or bench surface with something resting against the tank to stop it rolling off and falling onto the floor. Modern speargun tanks are light and roll very easily!

Find somewhere clean to place the very oily inner barrel, power regular block and rear handle assembly. Now you can see all the inner "works" and can carry out whatever you had to do which required getting inside the gun. A large plastic laundry bucket makes a good container to sit the dismantled gun in, you can buy inexpensive ones and just use them for your speargun work, that way it will offer a clean container which is easily washed out afterwards to remove any oil. If you cap the glass jar then you can re-use the oil poured out of the gun, especially if it is very clean and has no obvious contamination.

If you want the tank tube to line up in the same position as before with respect to rotation on the gun (for sticker alignment) then mark the front sight position on the nose cone end of the tank tube with some adhesive tape and do the same for the rear end adjacent to the rear sights on top of the grip handle. Putting the gun together push the tank on with the rear end correctly lined up as it is often hard to twist the tank around afterwards due to the two or three main body "O" rings at that end of the gun. It is a different story with the nose cone as once pushed on you can line it up by twisting it. Remember to tip the oil back into the gun before replacing the nose cone, then screw the muzzle back on and you are ready to re-pressurize the gun.

Use clean newspaper to make a temporary work surface (floor and bench top) that will catch any spilt oil and have some cloth rags for wiping parts clean, cotton garments that have worn out make good rags as they are lint free as they have lost most of their surface fuzz, hence are as the saying goes, "threadbare". Do the work where you will not have any dust or dirt blowing around as the oily parts attract such things like a magnet and then you will have to wipe everything clean of any oil before reassembling the gun. With pneumatic speargun maintenance cleanliness is everything as seals are unforgiving of contaminants getting between them and the seating surfaces they sit on or abut against.
 
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devondave

New Member
Oct 5, 2007
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0
Bromley UK
Thanks Pete.
Very useful description, sure to be a db reference for future use.

Pete, what do you think about using the pump to put the oil in the gun after assembly?
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Thanks Pete.
Very useful description, sure to be a db reference for future use.

Pete, what do you think about using the pump to put the oil in the gun after assembly?
I have used that method of sucking oil into the handpump and then on the next pump stroke pushing it into the gun. On some handpumps you can unscrew the rear end, remove the pump rod while the handpump is still connected to the gun and pour oil in through the open back end of the pump. Then you know exactly how much you have added. Reassemble the pump rod into the handpump barrel and with the next stroke the oil goes in. Although I have never had it happen to me, I have heard that in some situations the oil flow can tilt the small "O" ring that the inlet valve ball sits on so that the valve no longer seals. That never happens when pumping air. If you give a steady press on the pump handle and push the oil in gradually, there is no need for a fast pump stroke, then I think that such "O" ring seal displacement is very remote. On the valve stem inlet valves this can never happen as the projecting shaft of the stem stops the "O" ring tilting over, however most Italian pneumatic spearguns no longer use the stem type inlet valve. The advantage of these older style inlet valves is that you could bleed air out using the unscrewed spear tip to depress the valve while still in the water, you do not want to do that with a ball type inlet valve or you may mark the smooth surface of the inox ball. An aluminium knitting needle has a smooth bullet shaped nose which will not damage the inox ball, so use that to depress the valve, or a wooden toothpick using the wider end. Small successive bursts of air release are best, never push the inlet valve in too far. That way you have better control over compressed air release and do not envelop yourself in a big cloud of atomized oil! While you usually get oil on you while doing gun dismantling work it is better not to breathe the stuff in if you can avoid it!
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Repairing a Mares "Cyrano" will require a slight variation on the "low pressure air assist" dismantling method that I described earlier on this thread. This is because the "Cyrano", unlike most other pneumatic spearguns, has a two-piece forward nose section. The black plastic outer nose cone with the integral tubular handhold extension sticking out the front of it which in turn carries the front sight and line wrap hook is never exposed to the gun's tank pressure. This is because the rear inner end of the nose cone is "O" ring plugged near its outer periphery by an insert that is the true forward pressure bulkhead in the "Cyrano" gun. The insert itself is a moulded white nylon "tall top hat" shape with 8 longitudinal rib reinforcements stopping what would be the "brim" of the "hat" distorting under the influence of tank pressure acting on its essentially flat rear face. The step on the upper or front face of the "brim", which has its own radial rib reinforcements located underneath on the pressure side (there are also 8 of them), fits into a corresponding step in the rear end of the black plastic nose cone and that is where the "O" ring is located that hermetically seals the two of them together. Hence unlike other pneumatic guns the actual nose cone contains neither high pressure air nor lubricating oil sloshing around inside it; the internal space between the insert and the nose section being at whatever pressure the gun was assembled at, namely atmospheric pressure.

If the "Cyrano" is "low pressure air assist" disassembled with the muzzle pointed towards the ground then the sealing "O" ring between the insert and nose cone will separate once the nose cone begins to move and oil as a consequence will flow down into the nose cone. To avoid this happening the "Cyrano" needs to be held with the muzzle elevated while using the hand pump to generate sufficient air pressure to push the nose cone off the gun, that way you keep the oil sitting in the back end of the gun. With just the right amount of internal air pressure you can unscrew the muzzle from a small starting gap with only your fingers and the nose cone will follow along behind it like a dog on a lead, then after about a centimetre of forward travel you can let all the air out and then twist and pull the nose cone up and off the inner barrel tube. The white nylon insert, which will not have moved, can then be slid forwards on the inner barrel tube, which will then fully open up the mouth of the air tank and you can up end the gun to tip the oil out into a collection jar rather than having to pour it out over and around the restriction of the insert which would only leave a small annular gap to the ID of the air tank.

If this is done properly then the nose cone will be removed with oil only on its outermost rear periphery (which does face tank pressure) and with no oil on the front or longitudinally ribbed end of the white nylon insert making for a far less messy dismantling of the gun. Plus you can then confirm for yourself that the front and heavily greased "O" ring on the inner barrel tube just keeps water out of the nose cone's "empty" interior while the second "O" ring on the inner barrel, located some distance behind it, is the one that actually functions as a seal for the high pressure air.

I can only assume that this two-piece forward nose section "Cyrano" design is to avoid the possibility of high pressure air accessing and cracking the small OD cylindrical handhold extension on the nose cone which would otherwise have to serve as a plastic "mini-reservoir tank". Although the "Cyrano" is a nice looking gun, I never thought that the long snout was a good idea as it stole a lot of reservoir capacity from the gun, particularly as the front end of the inner barrel tube is 20 cm from the innermost barrel "O" ring position which marks the true front termination of the internal air reservoir!
 
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popgun pete

popgun pete

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Jul 30, 2008
2,767
524
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Australia
"Cyrano" top hat bulkhead as removed, but minus rear "O" ring in the back end that seals on the inner barrel tube and sits in the central well. Note that rear face is oily while forward ribbed section is only smeared with grease from the factory. Interior of black plastic outer nose cone is mainly oil-free as this white structure plugs it sealing at the "O" ring seen at the base of the long outer ribbed section.
 

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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
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153
Australia
I never posted this section about taking the rear handle apart as I thought that I had already written about it somewhere else. In the Mares tool kit (which I do not have) there is a tube spanner, basically a pipe with 2 lugs on the front end that engage in the slot cut across the rear exposed metal face of the inlet valve body. A T-bar passing through the rear of the tube spanner allows you to apply twisting force which will undo the inlet valve body from the rear plastic grip, the valve body will unscrew from the internal threads in the rear end of the inner barrel tube, the latter being only a push fit inside the rear plastic grip moulding. Once you have the inlet valve body removed you will see that looking at its inner end there is a black plastic part that screws out of the metal valve body, it has a screwdriver slot as well as a small hole in its face. This plastic part is the retainer for the inlet valve's inox ball, conical return spring and small "O" ring that provides the seal for the rear air valve. On some guns like Seac Sub there is a small circlip rather than a screw thread to hold the plastic retainer inside the inlet valve body.

If you do not have a tube spanner then a rectangular piece of metal (steel, brass) can be used along with some vice-grips to provide a twisting handle, the end of the metal bar has to engage the slots very closely or it will cam out and damage the slots, so you need something of the correct thickness which you can cut to shape and insert in the rear gun port.

Not only does the inlet valve body secure the inner barrel in the gun, tightening it up also pulls up the power regulator partitioning bulkhead firmly against the front internal face of the rear plastic grip molding. To free the partitioning bulkhead the inner barrel is pulled forward out of the grip and then the partitioning bulkhead is pulled rearwards off the inner barrel tube. But before doing this you must remove the small diameter trigger transmission pin by pulling it out of the grip, which requires removing the plastic trigger and trigger pivot pin first (just knock the pivot pin out with a drift and light hammer). Not doing so risks bending the trigger transmission pin as it sticks up through a slot cut into the inner barrel tube. The edge of this slot which will catch on the pin and could bend it if you pull the inner barrel out of the rear grip too soon.

The large metal or plastic circlip on the inner barrel creates the diameter step that retains the partitioning bulkhead on the inner barrel so that it can only slide so far forwards before it is locked in place inside the gun. This circlip can only be removed after the partitioning bulkhead is moved away from it, which requires the inlet valve body to be removed first, so do not try and remove the circlip any earlier in the disassembly process.
 
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popgun pete

popgun pete

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Jul 30, 2008
2,767
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As indicated above removing the inner barrel from the rear handle molding allows the partitioning bulkhead (power regulator block) to be pulled off the rear of the inner barrel tube. But before doing so the sear pivot pin must be knocked out first as it often projects either side from the inner barrel just enough to foul on the inner bore inside the partitioning bulkhead. Note that on "Cyrano" guns the sear pivot pin is on a chord drilling to reduce the trigger pull, not on a diameter drilling as before, instead being located slightly below it. This height change lowers the restoring torque as the piston tail under pressure in the cocked gun opposes the motion of the sear lever being tipped over by the trigger transmission pin when you fire the gun. I assume all the later Mares guns using the "Cyrano" shape handle have this sear pivot pin height modification. (The Scubapro "Magnum" was one of the first pneumatic guns to use it, the "Magnum" being a complete redesign of the "Sten" with many detail changes to the shapes of the internal components. The idea was first used on single-piece trigger band guns, which is not surprising as the Mares pneumatic gun sear levers are essentially flattened single-piece triggers with a very short push rod penetrating the pressure chamber and being activated by an external remote trigger.)

The last remaining item in the gun dismantling process is the power regulator shaft and piston. The piston is turned with a small open ended spanner using the flats on the rear of the brass piston. Ideally the piston and control shaft can be screwed out as a single unit by separating it at the screw threaded connection to the power regulator knob or cursor that sits in the right-angled selector gate. A replacement "O" ring can then be pushed onto the regulator shaft from the rear end of the shaft. If the threaded connection to the cursor is very tight then the brass piston may screw off the front end of the 4 mm OD stainless steel shaft instead. In this situation use a small electric drill's three-jaw chuck to grasp the bare end of the power regulator shaft (well forward of where it will eventually slide through the "O" ring seal) and twist the chuck by hand to forcefully undo the shaft from the cursor's male threaded inner end. This method of gripping the shaft with a chuck avoids scratching its smooth surface which is particularly important if an "O" ring is subsequently pushed over the affected area during reassembly.
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Note that on "Cyrano" guns the sear pivot pin is on a chord drilling to reduce the trigger pull, not on a diameter drilling as before, instead being located slightly below it. This height change lowers the restoring torque as the piston tail under pressure in the cocked gun opposes the motion of the sear lever being tipped over by the trigger transmission pin when you fire the gun.
It appears that the reason for the apparently lower sear lever pivot pin height may be somewhat more prosaic. I have checked the sear lever part numbers and they are identical, the "Cyrano" and "Sten 2001" use the same part "43163377" for their sear lever (or catch hook). With the same tooth height the "Cyrano" sear lever pivot pin has to sit slightly lower down in terms of the barrel's outer curvature in what is a smaller diameter barrel tube for the "Cyrano". In fact the sear lever is the same part number from the previous version ("Sten 87" and "Reef") if we ignore the "43" prefix, i.e. "163377". The earliest "Sten" has a different part number "163313" for the sear lever, so it must be slightly different. I have never checked it, but maybe I will as I have one that can be dismantled as it is out of action and has been for years.
 

tromic

Well-Known Member
Aug 13, 2007
1,540
149
103
Croatia
Sometimes a pneumatic speargun will be difficult to disassemble easily because the parts are a tight fit (like in a Mares "Mirage"!). I have found this method useful on most rear handle pneumatic models.

First release all the air with any power selector set to "maximum" as this ensures that all the air chambers in the gun are connected to each other, that way you will not leave any compressed air inside the gun. Then take the spear or a blunt ended rod of similar diameter and push the piston back so that it just disappears into the inner barrel and leaves a clear view through the muzzle's relief ports. Using a metal rod, or a screwdriver that is a reasonably close fit in the relief ports, pass it through opposing relief ports to provide a handle whereby you can unscrew the muzzle by hanging onto each end of the rod or screwdriver (round shaft Phillips head type, not a blade tip screwdriver). Sitting down on a chair you can trap the grip handle between your feet as you apply a twisting torque to undo the muzzle while holding the gun vertical between your knees. Generally the muzzle will come off easily after only a few turns, so you can unscrew it the rest of the way with your fingers. Put some fresh grease on the exposed muzzle threads and then screw the muzzle back on. When the muzzle contacts the nose cone, you will feel the muzzle stop turning, back the muzzle off a number of turns to leave a gap. Now take the gun's handpump and screw it into the rear of the gun. With the muzzle pointed downwards and resting on a rubber surface like an old thong (the "flip-flop" footwear type) begin pumping using slow strokes and watch the muzzle nose cone. A small amount of air pressure in the gun will cause the nose cone to slide down the inner barrel tube and out of the tank, the reason that you only unscrewed the muzzle by three or four turns was to make sure that the nose cone did not come right out of the tank or you would have oil everywhere, plus you want the piston to stay in the inner barrel bore without the piston seals emerging for the exact same reason.

Now remove the handpump and release any air from the gun as before, there will be very little pressure with only a small number of pump strokes. Unscrew the muzzle and remove it, then twist and pull the nose cone and slide it up over the inner barrel threads. You will find that the "O" ring on the inner barrel tube has chased the nose cone part way up the inner barrel threads, that is why you greased them earlier. Make sure that the nose cone has its outer "O" ring, sometimes it falls off and will be inside the tank, in which case you will need to retrieve it later. Pull the piston out of the inner barrel and up end the gun over a clean container like a glass screw top pickle jar to collect the oil. Leave it for a while to fully drain the oil out of the gun, then return the gun to the barrel up position and screw the muzzle back on to about half distance on the screw threads. Now hold the gun by the front of the tank in one hand and strike the muzzle nose with a soft faced hammer (preferably a nylon faced, double sided hammer like a "Thor", that is what I use). A few good hits and the barrel and handle will drop out of the tank tube, make sure that it does not have too far to fall and then the rear of the muzzle will not hit the front end of the tank. I hold the gun just clear of the floor with a rubber thong directly underneath the grip for the back of the handle to fall down onto, that way there will be no damage to anything. Unscrew the muzzle, put it to one side and carefully lift the tank clear of the inner barrel and place the tank on a level table or bench surface with something resting against the tank to stop it rolling off and falling onto the floor. Modern speargun tanks are light and roll very easily!

Find somewhere clean to place the very oily inner barrel, power regular block and rear handle assembly. Now you can see all the inner "works" and can carry out whatever you had to do which required getting inside the gun. A large plastic laundry bucket makes a good container to sit the dismantled gun in, you can buy inexpensive ones and just use them for your speargun work, that way it will offer a clean container which is easily washed out afterwards to remove any oil. If you cap the glass jar then you can re-use the oil poured out of the gun, especially if it is very clean and has no obvious contamination.

If you want the tank tube to line up in the same position as before with respect to rotation on the gun (for sticker alignment) then mark the front sight position on the nose cone end of the tank tube with some adhesive tape and do the same for the rear end adjacent to the rear sights on top of the grip handle. Putting the gun together push the tank on with the rear end correctly lined up as it is often hard to twist the tank around afterwards due to the two or three main body "O" rings at that end of the gun. It is a different story with the nose cone as once pushed on you can line it up by twisting it. Remember to tip the oil back into the gun before replacing the nose cone, then screw the muzzle back on and you are ready to re-pressurize the gun.

Use clean newspaper to make a temporary work surface (floor and bench top) that will catch any spilt oil and have some cloth rags for wiping parts clean, cotton garments that have worn out make good rags as they are lint free as they have lost most of their surface fuzz, hence are as the saying goes, "threadbare". Do the work where you will not have any dust or dirt blowing around as the oily parts attract such things like a magnet and then you will have to wipe everything clean of any oil before reassembling the gun. With pneumatic speargun maintenance cleanliness is everything as seals are unforgiving of contaminants getting between them and the seating surfaces they sit on or abut against.
Back to this threat. I was just thinking about the safest method regarding the gun. Unscrewing the muzzle is the most critical step in dismantling. There is a high possibility that inner barrel would turn with the muzzle what would cause a damage to trigger mechanism parts and a plastic part in a handle that protrudes and is engaged with inner barrel slot to ensure the right position of the inner barrel. Peter, you migt explain this better. I would advice as a safest method in dismantling the speargun to start with removing the rear handle first: trigger mechanism, inlet valve, handle itself, ... Removing the handle must be without rotating movement regarding the muzzle and inner barrel. Only gentle wobbling movement is allowed.

Still another useful hint, from a guy from Italian forum (Cyranosub), is to use two vices. One to fix a handle, and another to fix a inlet valve. After handle and valve were fixed unscrew the muzzle of the gun. This is much better than fixing just the handle while unscrewing the muzzle.
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
The inner barrel is stopped from turning in the rear handle by an indexing peg in the rear of the molding that fits into a notch cut into the rear of the aluminium inner barrel tube. In modern guns there are two pegs and two notches at 180 degrees to each other, unlike early gun which only had one at the bottom. The plastic pegs (or peg) have to snap off for the inner barrel tube to turn and it takes a big effort to break them. What can cause them to snap is the muzzle to barrel connection threads have corroded and seized, then the muzzle and inner barrel will turn as a single unit, which you do not want. That will only happen if the muzzle has been screwed on without grease or an anti-seizing compound coating the screw threads first. Guns are assembled at the factory with this coating, but if the gun is later dismantled or a new muzzle is fitted and the threads are not coated then saltwater can creep in along the threads and corrode them over a long time period. One of the reasons for a two-yearly oil change is to open the muzzle up and re-grease the screw threads. If you do that then you have little possibility of the muzzle screw threads seizing up, don't do it and five or six years later you may have seizing problems.

If when dismantling the gun the muzzle does not come loose after an initial twisting effort to remove the tension on the inner barrel tube, then you have to go in via the rear inlet valve body. That means removing the trigger pivot pin, trigger and trigger transmission pin first, only then do you unscrew the rear inlet valve body. This is a messy business as some oil will flow out of the small hole that the transmission pin passes through as some oil is always trapped in the confines of the rear handle molding. By removing these items first you avoid turning the inner barrel and bending the trigger transmission pin if things have seized up internally. It is more difficult for saltwater to move in along the rear inlet valve body threads than the muzzle threads as the latter are exposed at their outer ends to the environment inside the muzzle opening, but guns can have saltwater penetrate into their interior if they depressurize at depth and then all options are open for internal thread corrosion throughout the gun. After such an incident, which hopefully is very rare, you need to disassemble the gun as soon as possible to remove all traces of saltwater in the gun. I have had to do it twice!

The key thing is apply grease to the muzzle connection threads, then you will have no problems afterwards. Of course always let all the air out first, I know people who complained of a tight to turn muzzle when the gun was fully pressurized, fortunately for them they got no further! Do not use multigrip pliers on pneumatic speargun muzzles, you will only mangle the surface finish and will fail to notice the piston is obscuring the muzzle relief ports, which means air pressure in the gun. As for dry or vacuum barrel kits you need to use a suitable tool on the muzzle after you have pushed the piston back with the spear and make sure that it stays back, otherwise disaster awaits! By staying back I don't mean latching the piston on the sear lever catch or you will have problems, in other words never cock a gun and then open it up unless you immediately depressurize it first.
 
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tromic

Well-Known Member
Aug 13, 2007
1,540
149
103
Croatia
Thanks Pete! Cressi sperguns are safer for dismantling than Mares. I haven't dismantling Seac Asso jet, but I have heard they were also different, I suppose safer not to make damage caused by turning of inner barrel like with Mares.
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Thanks Pete! Cressi sperguns are safer for dismantling than Mares. I haven't dismantling Seac Asso jet, but I have heard they were also different, I suppose safer not to make damage caused by turning of inner barrel like with Mares.
They are all very similar in construction, the only inner barrel that cannot turn is in the Scubapro "Magnum" as the sear pivot pin in that gun projects well outside the inner barrel tubing and engages in long slots on either side of the handle molding. To turn the inner barrel you would have to bend the ends of the pivot pin or break the molding, both are reasonably substantial in construction. Having damaged guns through ignorance I learned by my mistakes, that is where this information all comes from, it is the product of experience, not theory.

I have now added a thread on the main cause of tight to remove muzzles: http://forums.deeperblue.com/pneumatic-spearguns/95063-alert-dry-vacuum-barrel-kit-users.html. This advice is also extended to oil change muzzle removal operations.
 
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tromic

Well-Known Member
Aug 13, 2007
1,540
149
103
Croatia
They are all very similar in construction, the only inner barrel that cannot turn is in the Scubapro "Magnum" as the sear pivot pin in that gun projects well outside the inner barrel tubing and engages in long slots on either side of the handle molding. To turn the inner barrel you would have to bend the ends of the pivot pin or break the molding, both are reasonably substantial in construction. Having damaged guns through ignorance I learned by my mistakes, that is where this information all comes from, it is the product of experience, not theory.

I have now added a thread on the main cause of tight to remove muzzles: http://forums.deeperblue.com/pneumatic-spearguns/95063-alert-dry-vacuum-barrel-kit-users.html. This advice is also extended to oil change muzzle removal operations.
Something similar is with Cressi too. Thanks for a new thread too! :friday
 

tromic

Well-Known Member
Aug 13, 2007
1,540
149
103
Croatia
Still another way:

[ame=http://www.youtube.com/watch?v=pgSLsaml0f8&feature=player_embedded]ОбÑлуживание Ñ€ÑƒÐ¶ÑŒÑ - YouTube[/ame]
 

leegirl

Member
Jun 11, 2013
2
0
11
South australia
Hi can someone please help me? i just bought a Asso Seac Sub 90 and i pulled the plastic off and hardly even touched the trigger and it went off in my loungeroom along with pieces of white plastic lol thank heavens without the spear in... im guessing that the piston has shattered something the muzzle? there was no manual inside the packaging and would you believe that i have not seen the recipt since i put it in my car i spent days looking! i'm still looking!
 
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popgun pete

popgun pete

Well-Known Member
Jul 30, 2008
2,767
524
153
Australia
Hi can someone please help me? i just bought a Asso Seac Sub 90 and i pulled the plastic off and hardly even touched the trigger and it went off in my loungeroom along with pieces of white plastic lol thank heavens without the spear in... im guessing that the piston has shattered something the muzzle? there was no manual inside the packaging and would you believe that i have not seen the recipt since i put it in my car i spent days looking! i'm still looking!
Assuming that it is new take it back to the vendor as it should be replaced or repaired under warranty.