• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

Mares Bazooka

What some owners may not have realised is the grip handle comes off the Titan guns in order to adjust the trigger operation. This was done at the factory in order to get the trigger pull stroke to fire the gun without creating a hair trigger. Because powerful springs on the gun's pull rods that travelled rearwards from the mid-handle were there to resist internal pressure blowing the pull rods out of the gun a balanced spring tension adjustment had to be made and then the trigger re-engaged on the pull rod screw threaded adjuster which required the pull rod being pulled forwards slightly to engage the metal tab on top of the plastic trigger. A bit of trial and error was required to get it right if the gun had been totally disassembled including losing the tension adjustments on the long coil springs. Not a gun for the faint-hearted to play around with as you could easily get it wrong. By way of comparison a Mares rear handle Sten was a cinch to work on..
Titans with grips removed R.jpg

Titan centre sections and trigger pull rods R.jpg


Bazooka grip and handle fixing bolt R.jpg
Last edited:
  • Like
Reactions: Zahar and tromic
great report Peter, I am really happy the Bazooka went to a connoisseur like you. Now I have to admire also your Hydra, another legend of my early years ! Ciao!
  • Like
Reactions: tromic
The Mares pneumatic spearguns were originally offered with a couple of moulded plastic loading handles, a tubular one with horns being that supplied with the Titan models which could also double as a muzzle cover when the gun was in storage. It is seen in the photo second fron the right on the lower row as well as the far right on the top row. One advantage of this rocket shape was it increased your reach to the tip of the ready to cock pneumatic speargun.
various hand loaders 4R.jpg
Pneumatic spearguns are much easier to dismantle in warmer weather as everything moves much easier due to the thermal expansion of alloy parts and the softening of rubber seals. The dimensional changes are tiny, but make a big difference in twisting and pulling tight fits apart. Next is the muzzle on the Bazooka and why is it so big, yet at first glance the muzzle relief ports look tiny.
Last edited:
Thinking to open up the Bazooka I had already depressed the inlet valve and found no air in it, but having been misled in the past I tried pushing a small Miniministen shaft into it to explore the piston movement and found resistance, not a huge amount, but the gun needed a good push held vertical driving the gun down on the spear, so the gun has air in it, in fact quite a lot of it. Now I have a problem, how to get that air out! Fortunately, although rarely, I have struck this problem before, but never on a Mares gun. What is happening is the inlet valve "O" ring, after unknown decades, has deteriorated and stuck to the ball valve stem. When I depress the ball valve the '"O" ring moves with it and the gun pressure causes the rubber ring to distort moving back and plugging up the gap created by the steel ball lifting off, so the seal never breaks. The only cure for this is to jiggle the inlet valve ball until it begins to leak, not much, but a tiny leak. As this could take weeks to bleed down enough for the rubber ring not to seal the answer is to set the gun power controller to load or low power. That means the leak only has to bleed down the inner barrel and brass cup pre-chamber, in fact that is in progress as I type this up. Last gun that gave me this headache was a Russian Seabear 103 practically bursting with 40 bar plus in it, a pressure foolishly suggested by the US instruction booklet, but absolutely forbidden by the original language Russian instruction booklet. As that gun has no partitioning bulkhead I spent many hours jiggling its inlet valve allowing the tiniest amounts of air to escape. Once gun pressure could no longer squeeze the rubber seal back on its seat the air then left the gun in a rush.
Last edited:
  • Like
  • Haha
Reactions: tromic and Zahar
After a half day of jiggling the inlet valve stem and getting a puff of air out before it sealed again I switched to a rounded tip instead of a flat one on my valve pushing tool and then air came in longer bursts. Once that happened I set the gun to full power as the selector lever will not move easily in the gate with the inner barrel empty due to the strength of the pull rod springs. Then air came out in much longer bursts and finally it continually streamed out and the gun is now empty. Now I have to find out why that happened, so next the inlet valve body comes out. Unlike the Sten it does not hold the gun together, it just screws into the plastic tail cone. This is the weakest part of the Titan design, if the plastic tail cone screw threads strip then the gun is toast, as a new tail cone would be rarer than hen's teeth.
Mini Titan Sheet AR annotated.jpg
Last edited:
  • Like
Reactions: Zahar and tromic
An advert that Don Paul found which I have cleaned up. So Mares claim a range of 16 to 20 something which given that it is a US advert will be in feet. The 10 mm diameter shafts are very heavy!
mares advert.jpg
How are things going?? I only checked that the piston was working fine and seemed with very low pressure, so I did not try to unload it further. I hope you were able to repair the valve. The original shafts are really solid. I might be worth to try with an 8mm . I just got a Cyrano 120 with 7 mm shaft and it swings a lot when I try to load it ;-)
How are things going?? I only checked that the piston was working fine and seemed with very low pressure, so I did not try to unload it further. I hope you were able to repair the valve. The original shafts are really solid. I might be worth to try with an 8mm . I just got a Cyrano 120 with 7 mm shaft and it swings a lot when I try to load it ;-)
I have taken a break on it, but now with the arrival of hotter weather things become easier to take apart as the alloy tubes expand. Not by much, but it makes a super tight fit just a smooth press fit. I would say that the Bazooka has never been fired and never been wet, brass parts are as shiny as they were the day they were made and that air has been in it from the beginning, and it was under more than just token pressure. What can happen is the inner barrel can slowly leak down with maximum pressures still in the outer tank. To avoid that happening you leave the gun on full power, forward and down in the gate, but nobody ever does that. It is a weak point on these Titan guns because the selector gate uses a pull rod, not a push rod, albeit a very short one in the Sten and its myriad clones.

I don't intend to shoot the Bazooka, it is a nice looking gun, but way too long to be useful these days. In the past you would have entered from a boat, have someone hand you the Bazooka and headed for an already scouted lair where some holed up monster glowered from within. Eventually deciding these puny creatures outside were nothing to fear it would sally forth where it was met with a barrage of steel from guns like the Bazooka and Hydra. Making for its next lair, they have more than one home, it would be bending and busting spears as it was bludgeoning its way through the reef. A lucky shot might take it out through the brain box or an eye, then weakened it would finally succumb. Once cheered to the echo you would now be booed from all sides.
Last edited:
Weather has been up and down in nothing like Summer, but that is par for the course in Melbourne where you can have four seasons in one day. Sounds like a joke, but it is true, so no more work on the Bazooka. Usually I would be on my way to diving mecca Coffs Harbour by now.

One thing I learnt is you insert the spear tail slightly deeper than usual to hit the piston face and the muzzle can then hold it sticking out on a cantilever. Given the shafts are 10 mm in diameter that is a lot of weight hanging on the muzzle before you even start to load the gun, so that is one reason for the heavy muzzle construction which is in order to support that shaft weight A 10 mm shaft is 56 percent heavier than an equivalent 8 mm shaft, you work this out from the ratio of the diameters, i.e. 100/64 which equals 1.5625. No wonder the gun can only shoot 20 feet.

The supported loading length is the big killer on this gun, plus holding it over your shoulder to shoot it in the point and shoot manner as you cannot hold the gun out in front of you. The Bazooka name was well chosen, but the users of 2 metre long spring guns faced this same problem as well. Once you go beyond the rear projection of the gun rearwards from the mid grip handle to your arm length you are going to have the back end of the gun running into your mouth. The Nemrod Mariner III big banger flirts with taking your teeth out for this very reason, it is nearly as long as your arm, unless you are a gorilla. Just to be sure the Mariner had plenty of oompth it has a 50 mm tank diameter, standard tanks are 40 mm.
Pneumatic speargun dimensions diagram.jpg
New Year's Day and our Bummer Summer seems to have ended with grey skies and maximum temperatures in the low twenties for the last couple of weeks. Also we have had flooding downpours, so lawns are growing like crazy.

I decided to take some photos of the Bazooka and Nemrod's Mariner III which was that company's last effort at a monster slayer. Only the Bazooka could make the Mariner III look small and both these guns were around at the time dinosaurs ruled the Earth, or it seems that way. The Mariner III is a huge gun with a 50 mm diameter rear tank and the rearward extension of the tank places the rear valve cap just under and slightly forward of your chin, and in the take aim position with you looking up and forward that rear end will touch your snorkel. So now you know why few used the big Mariner and why even fewer used the Bazooka as you have to shoot the latter Bazooka style, i.e. over your shoulder.. Absolutely no way to sight along the barrel, it is convergent line shooting or nothing. Plus both these guns are very heavy and shoot big spears, having pulled the trigger you then have reloading to look forward to.
Mares Bazooka and Nemrod Mariner III R.jpg

Mares Bazooka and Nemrod Mariner III rear tank projection R.jpg
  • Like
Reactions: Zahar
The Bazooka has a larger diameter muzzle and the black nose cone is alloy and surprisingly the relief ports are in the nose cone, not in the muzzle. Looking into the muzzle I can see a cadmium plated finish ring, which is the end of a tube and the relief ports pass through that, there are only two of them and they are rather small. I took two grub screw out of the chrome plated sight and line anchor frame and can twist it on the alloy nose cone, but have not been able to pull it off, although I have limited the effort there. I got the muzzle to budge slightly with a 28 mm spanner using flats on the extreme nose, but will not try more force until I figure out what screws into what. No hot weather lately, in fact rain for many days, but my impression is the muzzle assembly, including the nose cone, are there to support the cantilevering weight of a spear placed in the muzzle before you commence pushing with a hand loader. I know it can take that load as I had the gun sitting on a chair angled upwards with the shaft stuck in the muzzle with my hands completely off the gun and it just sat there. My guess is the gun uses water pumping to protect the muzzle, the opposite of what is usually the design aim used for pneumatic gun muzzles. That may explain the cadmium tube inside the muzzle as it sure ain't alloy. It has never been wet and never had saltwater in it. The back pressure of water in the barrel during the shot will kill the gun's power, but steel inside the muzzle suggests Mares were worried about blowing the end off the Bazooka gun. Will know more once I screw the nose off, but I don't want to bust anything, so once I can get it to turn freely for a few turns then I can take it right off.
Mares Bazooka muzzle.jpg
Last edited:
  • Like
Reactions: Zahar and tromic
Now turning my attention to the Bazooka, applying a moderate degree of force does nothing to turn the muzzle, but as this gun has never been used there may be a trick to undoing it as it surely has zero corrosion. I greased the exterior of the muzzle and nose cone and got that chromed fitting to slide and turn, but right now it will not revolve fully and possibly the grub/set screws I removed had previously on initial assembly kicked a bit of metal up and applied the stoppers. I also think the slot in the chromed fitting is catching on the matching trough cut into the nose cone as it slides forward and then stops when the edges hit. I expect when Mares assembled it they bashed it on with a drift, but I don't have a sliding hammer to go back the other way.

We can deduce that with relief ports in the nose cone they have to match some in the inner barrel, I have seen that on Soviet era guns, but they were weak. The relief ports have to be behind the shock absorber anvil, so my guess is the piston nose is long enough to reach across a separate section that holds the relief ports and that section is not the inner barrel, but something screwed onto the front end of it. So there must be two nose threads, one on the alloy inner barrel and one on the port carrying tube that sits immediately in front of it. I found a Bazooka diagram, but it showed nothing of the nose cone, just a schematic which was useless.
Last edited:
Just searching around for more Bazooka info and I found that the late Don Paul wrote about his gun on another forum, but only showed photos of the handle and the brass cup partitioning bulkhead in the tail end of the gun. However he did mention a sprung loaded snubber and in the context of firing heavy spears. I think that means a coil spring in the shock absorber body rather than stacks of rubber washers. Now spring shock absorbers date back to the earliest mid-handle pneumatic guns and that would explain the big muzzle body diameter and the load I can feel opposing my efforts with the wrench. A gun that most would know from the James Bond heroics is the Technisub Jaguar and that certainly has a spring in the shock absorber seen here in its parts diagram, part number 11. That then means the nose on the Bazooka muzzle is being pushed against its screw threads by a big spring under some tension, so that is not the way to get the nose cone off. More thought is now required.
Last edited:
It is pretty clear now that Mares treed themselves when they put the Bazooka out. The Titan guns were a means to increase tank capacity of the classic layout pneumatic guns by adding more tank volume forwards of the grip handle. More tank volume, lower compression ratio, higher start pressures and thus more powerful shots can then result. As Mares had all the component parts they just had to use longer tubing lengths to create a range of gun sizes. Once they decided to lengthen the Titan, which was already a sinker, they had to put as much tank length out front as out the back, hence you get this monster, in order to provide a fore-aft balance. But what are you going to shoot with it and the only answer back then was big resident reef fish that for most intents and purposes were armour plated. To make a hole in them that hit something vital you were going to need shaft momentum at the target and that meant a big shaft. Now Classic layout rear tank guns often shot 9 mm shafts, but big fish had been known to just shrug those off with no apparent effect, so the next step up is 10 mm diameter shafts. When you introduce a long 10 mm shaft into the muzzle, and unlike an octopus you only have two arms and two legs, there will be a moment when that big shaft tries to twist the nose off the gun as there is no help from the water displacement up-thrust. Once Mares engineered for shooting long 10 mm shafts the die was cast, but why they resorted to a long stroke shock absorber is hard to fathom. A standard rubber sleeve shock absorber anvil may move a millimetre or so forward when hit by the fast moving piston, but a spring will collapse even more, and you don't want the front piston seal subsequently escaping the inner barrel bore or whoosh and all your compressed air is gone.

We know Mares made rear handle Stens up to 150 cm, but they don't have coil spring shock absorbers and their muzzle look like the usual Sten types, so it is that 10 mm shaft that decides things. Sten guns only shoot 8 mm diameter shafts because the shaft tail stop is sized at 9 mm and that has to pass through the hole in the shock absorber anvil body.

Those with long memories will remember that the big 2 metre long spring guns shot 10 mm shafts, and sometimes larger, but those shafts were hollow, they are not solid steel. The reason for the large shaft OD was the shaft was pushed down a barrel bore of that diameter, actually it was slightly larger, as was the coil propulsion spring, and they didn't want the shaft to rattle from side to side in the barrel tube.
Last edited:
I managed to find a led flashlight that I could put into the muzzle and now can see what is what, On the interior walls of the muzzle you can see the fat coils of the shock absorber spring which stretches some way back into the gun interior, That cadmium plated ring is the front face of the shock absorber anvil as a screwdriver shoved through the two relief ports passes directly behind it, so the nose cone of the Bazooka is indeed its muzzle and what I assumed was the muzzle is the shock absorber spring housing. I never thought about it before, but the inner barrel bore may be pretty large if it can swallow a 11 mm stop diameter on the spear tail. I assume Mares have a special tool that fits the side slots in the nose cone in order to screw it off. There are no other points of purchase bar the relief ports themselves. I don't have a bar that will go through those relief port holes. the one I normally use for my Sten's is too big, which means they are rather small holes!
After days of grease and oil getting into the nose end of the gun I used my biggest Crescent spanner to close up on the nose end flats and gave a strong pull and then everything undid with just my fingers. My guesses were all wrong as I never realised the relief ports, of which there are four, are in the muzzle which projects right back into the nose cone. With everything black as the Ace of Spades I could not see what belonged to what, but now everything Is explained. The side slots in the nose cone allow the ports to be exposed, but only if they line up on the slots. As the gun was assembled two were blocked off with only two in the horizontal plane showing, the others vertical and covered up by the nose cone!
Bazooka muzzle removal 1.JPG

Bazooka muzzle removal 2.JPG
Here is the nose cone without the muzzle inserted.
Bazooka nose cone 1.JPG

bazooka nose cone 2.JPG
Bazooka nose cone 3.JPG

The wet look of the nose cone is because I rubbed grease into it with the aim that it would wick down into the joins and spaces and that is exactly what happened. The muzzle when I backed it out was covered in oil and grease right to the bottom of the well in the nose cone. No sign of corrosion, or dulling of surface finishes, the gun has never been used. For that matter most of the Bazookas I have seen, mainly in photos, have not been used either as if they still have their metallized "Bazooka" sticker they are unlikely to have been used as the sticker comes off. Not sitting in a moulded recess, as on the original Sten's, the edges of the metal sticker get pushed up, crease and then fall apart because they are a very thin bit of alloy sheet.

I took that sticker off this gun because it was going to break up, it had already lost most of the "A" in Bazooka and just moving the gun around for photos another piece broke off and disappeared into my back yard.
Last edited:
And here is the muzzle which contains a big coil spring, much like the one shown on the Technisub Jaguar drawing, but even larger.
Bazooka muzzle 1.JPG
Bazooka muzzle 2.JPG
Last edited:
DeeperBlue.com - The Worlds Largest Community Dedicated To Freediving, Scuba Diving and Spearfishing


ISSN 1469-865X | Copyright © 1996 - 2024 deeperblue.net limited.

DeeperBlue.com is the World's Largest Community dedicated to Freediving, Scuba Diving, Ocean Advocacy and Diving Travel.

We've been dedicated to bringing you the freshest news, features and discussions from around the underwater world since 1996.