Pneumatic speargun mods

  • For bad vis, like 6ft, and holes or shooting inside structure I'd like to use a Mares Cyrano 700. It's a 70cm air gun with a 7mm single flopper shaft. I rigged it with two wraps of stainless steel cable so a big fish can't cut the line over sharp metal structure. It's hard to beat a pneumatic for short range punching power and the absence of bands makes it very maneuverable in tight quarters. One disadvantage is that it's nose heavy and if I carry it in ready to shoot position, which one must do in poor viz, my hand and forearm get tired. One further mod I need to do is to add some kind of form fitting flotation to the front of the barrel.



    Removed the safety and ground down the trigger which created a nice clean hole for attachment of the float line to the mono double loop. Took off the handle and wrapped tape around the handle stud to eliminate play in the handle.



    Ground down and reshaped the loader to fit properly into the handle. The big trick was positioning a metal receptacle in the loader because otherwise the spear point gets stuck and costs a few seconds to remove. The ready made loaders that come with this metal cup are always too big to fit in the handle. I made the cup from a piece of 8mm shaft by using different size drill bits to create a cone shape. It is held tightly inside the plastic loader with epoxy. Works very well.



    I wanted to see how well I could work the plastic. I ground down the sights and using sanding and Tin Man's steel wool method got the plastic looking almost original.



    Drilled a hole and put a stainless rod through it and bent it to form a retainer for the flopper. A notch on the flopper accepts this retainer and stays put nicely. In holes many times a fish will get skewered in strange angles and the shaft gets difficult to remove. With this feature its slides right back out the way it came. The SS cable is braided and crimped.



    The original line anchor is also theoretically supposed to hold the shaft when the gun is not in use. This doesn't function well as the shaft is not held tightly at all. Also the resulting line anchoring point is weak. I ground away the shaft retainer and drilled a hole as the new attachment point for the shooting line. I integrated a bungee into the hole. The bungee eliminates the need for a spring between the sliding line anchor on the shaft and the retaining ring.



    The bungee has the stronger and easier to disconnect pigs tail snap and swivel combination. The cable is braided and crimped.



    This is what a 20lb cuda did to the inferior conventional 400lb :rolleyes1: snap after wrapping the cable around structure.



    Since the above pics were taken I found another alternative to the sliding plastic line anchor and ring. This little sliding line anchor does the job of both and makes the spear more streamlined. It fits perfectly into the muzzle the same way the ring did keeping the shaft nice and centered without play.


    The piston adapter on the butt of the spear is ground down for a looser fit into the piston. This reduces the loss of power when the shaft leaves the piston. It also allows me to remove the spear from the gun while it's still in loaded condition. Last I changed the line release to the right to be consistent with my band guns and allow wrapping of the shooting line the same way; holding the gun with the left hand and wrapping with the right.



    All I'm missing is the flotation device I previously mentioned. If someone sources one please let me know.

  • Cool site. Never seen information about pneumatics organized so well. One thing that caught my eye that they're recommending is this mod with filing down the piston adapter.



    I have to call BS on that. It causes the sliding ring to stick on the adapter and then you have to bang it off with your knife. I know because when I started with my first gun, another cyrano but 970, it came with shafts that rusted and I had to sand them regularly. Without knowing I caused the same effect and the ring started to stick which was very annoying. It's what actually prompted me to move away from pneumatics in the first place as I didn't know the problem could be solved with a new adapter. Fun times..


    I saw the flotation thing they made, that's what I want to make but don't know which material to use, this synthetic cork stuff I never heard of it. I'll try searching for it. Oh yeah and it reminded me to shape the handle, that should take some of the stress off the wrist. It's too bad that these guns are very nose heavy because in a situation where they would be most useful, short range, the gun must be carried in the ready to shoot position continuously.

  • I know what you mean about having the sliding ring getting stuck, it got so bad that eventually the sliding ring shaped the adapter so it wouldn't get stuck anymore.


    I did two minor mod's from this website on my gun. The first one was enlarge the drain ports on the muzzle because my older model sten had tiny holes (way smaller than the newer stens and cyrano). When sent the gun in for maintenance, I also had them eliminate the pvc type material that's used in the High/Low power regulating system.


    The pneumatic guns I hunt with are over 120+cm and I hold them by the middle of the barrel most of the time. Even while descending, I'm still holding the gun by the middle and trying to hide it with my body so the bigger silhouette (having the gun extended) doesn't scare away weiry fish away. Only time I hold it by the handle is when I'm pulling out the gun and getting ready to shoot.

  • During my early days I used to shoot a 115 Sten gun.


    You are right on what you say about SVL modification on the slide ring. I told him that won't work, but it is still on his webpage...


    Now there is a guy in Spain that sells a kit that REALLY set the pneumatics one notch above. It consists in a muzzle that prevents the water to get into the barrel, so the problems with heavy nose and water evacuation are eliminated. The only disadvantage is that you can't use the gun for holes since the line is attached like on an Euro shaft, but just ahead the muzzle. I'll try to find the post in another forum and paste it here. Spanish, sorry for the americans, but Dan can translate the most important parts.


    On the other hand, every handle can be easily customized using two parts epoxy putty. I've done that with some of my guns and works great!

    Marco Melis

    A bad day fishing is ALWAYS better than a good day at work.

  • Love it! I've thought for a long time of attaching the shooting line to the shaft like that on a pneumatic. I use this system on a sling.



    I think it should be OK for short range in terms of accuracy. As far as the system for keeping the water out could you please explain what is going on in your pictures?

  • The guys name is Ramon(tocayo mio) and it's called Kara-yo kits. He also makes the Tovarich kits. I am currently trying to get one for my 115 cm Asso. They are basically similar to the Mamba but the Shaft ring/seal is made out of Brass and SS.
    Remeber I'm an older dude so pneumatics were the new thing for me for a long time. I mostly shot Pneumo's. I started with rail guns as a kid and I only got into the teak bluewater stuff, late in the game. Anyhow, he told me he's been sick lately but will soon start filling orders. His e-mail is Karayokit@yahoo.es. He also sent me a catalog. You can ask him for it or I can e-mail it to you.



    Cono se me olvido una cosa por estar hablando mierda. What do you guys think of the modifications that http://www.webalice.it/svl555/Sub/fucileenglish.html has?

    Edited once, last by Toledo970 ().

  • I'm interested to see what that's about. I heard a while back that there's a Russian mod that reduces the amount of sound produced when firing a pneumatic and I'm wondering if this is it. Please send me the catalog, I'll pm you my email.


    There are some modifications on that site that are nulled by mine. Another that I commented on that's BS. Apart from those there are quite a few. Can you narrow down which one you're interested in?

  • Except for the one you don't agree with(ring) everything else I guess.
    I just E-mailed you the catalog.
    There's a guy over on SB,Greekdiver(he has a video over on SB spearing with the Pneumo with kit), he's also on Medfish and has a few different kits(mamba,tovarich,karayo) I asked him which was the best and he pointed me towards the Karayo kit. It's Like the Mamba, but better construction. You could also interchange parts with Mamba. Maorisub(maker of Mamba) has other good products for Pneum. Check out there sight. The only down part, from what I've heard, is that they are difficult to deal with and take a long time. Also $$$$$ mucho bucks.

  • That's some good info. I know Harry and seen his gun. He did say it had a mamba kit at the time. It's hard to keep track of everything that's becoming available. When you get the karayo kit I'll be interested to get your impressions. Ease of loading, increase in power, decrease in sound if any and of course accuracy.


    I like the mods with the float and reshaping the handle. I had to carry the gun in ready to shoot position a couple of days ago and it really tired my wrist. The float would counter the muzzle's tendency to sink and reshaping the handle will provide leverage and decrease the stress on the wrist. I'd like to do a prettier job with the float once I find the right material, maybe make a cylindrical cut out that will allow it to snap around the barrel without needing zip ties. For the handle I will use the two part epoxy that you knead together.

  • Hey guys, Ramon from Kara-yo E-mailed me and it seems that he is going to be out of it for a while due to medical problems. I will E-mail him today to see what alternatives I have beyond Mamba.I will let you guys know how it turns out.

  • i have bougt a couple of things from ramon and he is a very nice guy with very good sevice,i got the tovarich kit for my asso 135 and it is very easy to instole and to use i also have a mamba with a karamba kit and im very happy the biggest improvment to me is accuracy i have made some shots that i would have never thogut posible.i prefer using ramon than maorisub.

  • I know what you mean about having the sliding ring getting stuck, it got so bad that eventually the sliding ring shaped the adapter so it wouldn't get stuck anymore.


    I did two minor mod's from this website on my gun. The first one was enlarge the drain ports on the muzzle because my older model sten had tiny holes (way smaller than the newer stens and cyrano). When sent the gun in for maintenance, I also had them eliminate the pvc type material that's used in the High/Low power regulating system.


    The pneumatic guns I hunt with are over 120+cm and I hold them by the middle of the barrel most of the time. Even while descending, I'm still holding the gun by the middle and trying to hide it with my body so the bigger silhouette (having the gun extended) doesn't scare away weiry fish away. Only time I hold it by the handle is when I'm pulling out the gun and getting ready to shoot.



    Here's a pic of what I was talking about:




    I did a couple of mod's on this gun and also had the maintenance done at my LDS


    1- Changed the handle to the older sten model & removed the plastic piece that makes the hi/low regulator work. I never use the gun in the low setting and without this piece the gun holds more air and shoot's harder IMO.



    According to my LDS, the original muzzle was damaged and needed to be replaced :rolleyes1: it turns out that the replacement part has smaller holes and it's not drilled at an angle to extract the water from the barrel like the original. Fixed the problem with some little porting work with my dremel and things are back to normal :cool2:


  • The blue handle looks nice. The old handle looks identical to the cyrano, it must be a Sporasub something..


    How much was the muzzle? Did you have to wait or did they have it in stock? Were you able to do the port enlargement with the muzzle on the gun?


    I want to remove the high/low switch too. Are the instructions on that website enough for me to do it properly?

  • The blue handle looks nice. The old handle looks identical to the cyrano, it must be a Sporasub something..

    Thanks Dan, the blue handle is from the old sten that was designed or used by Pipin in the mid to late 90's. The black/white handle is from the newer sten that were made the same time the cyrano had came out.


    I feel more comfortable with the older handle (blue) BC the original (black&white) has a small handle and my hand wraps around it a little too much and didn't want to duck tape the thing around the handle either. I also have a piece of flourecent rubber that went around another sten I had and that gives it an even better grip:




    How much was the muzzle? Did you have to wait or did they have it in stock? Were you able to do the port enlargement with the muzzle on the gun?

    Don't know how much the muzzle was, they had it in stock and yes I made the port enlargement with the muzzle on the gun. In reality the port's really weren't enlarged much, it's more of an angle that I made on the holes so the water is pushed up against a thin piece of metal out at an angle instead of a 90* turn. I'll post some better quality pics later to give you a better example or idea.

    I want to remove the high/low switch too. Are the instructions on that website enough for me to do it properly?

    Don't know what to tell you here, that piece was removed while I had them do the maintenance with the o-rings and all.


    :D

    Edited 4 times, last by Dan: resized pics ().

  • Thanks, I think it shouldn't be a big deal. I just wanted to know what's the best way to seal the holes. Two part epoxy putty should do it. Here are a couple of pics of it from when I took the 700 apart to change the inner barrel that got scratched and was letting out air. I took pics so as not to forget the order in which things go.




    Here's a chart that may be of interest.



    Here's a mod for those guys who really can't get over their wood guns :)


  • :laughing3: that wooden tape over those barrel's is hilarious


    I took the gun apart and changed the trigger assembly at home but then thought about not having the oil to fill it back up and going through the mission of pumping the air back in (the factory pump wont take it up to the amount of psi I shoot the gun with anyway).


    I've seen that diagram of the cyrano before and have it saved on my computer somewhere.



    It's good that you had those pics as a reference, i do the same with some major repairs i do on cars/trucks.
    Just incase you would like some type of video reference, here a link that might be helpful in the future:


    http://www.youtube.com/results?search_query=speargun+assembling&search_type=&aq=f


    it should be the top video's and it's a series of 4 video's all together.


    BTW these video's are from the same guy that has that website I posted earlier in the thread.

  • Those are some useful vids, thanks. My problem yesterday however was not assembling but disassembling. I'm talking about the Cyrano I found that's been in the water for maybe a year. The muzzle bonded with the inner barrel and I couldn't unscrew it. I forced it and it made the whole back end of the inner barrel turn inside the handle. I don't know the full extent of the damage but the trigger pin was bent and now the inner barrel can spin inside the handle. I had to disassemble the gun starting from the back. Fortunately I was going to remove the pressure reducer block anyways so it didn't matter that it got a little mangled in the process.


    The only way I could unscrew the muzzle was by sticking a metal rod through the trigger slot of the inner barrel and securing it in a vice. Then putting another metal rod through the port holes of the muzzle thus generating enough torque to unscrew it. It was so stuck that the force deformed the trigger slot slightly and I had to reshape it.


    Otherwise removing the block is easy and and so is sealing the hole for the pressure reducing rod/switch. It's a nice simple mod for those who do not plan on shooting the gun into a hole. If there are going to be any leaks as a result of this butchering it will be from the back of the handle or the trigger pin hole, although I straightened the pin and the trigger is moving smoothly. Since I didn't buy the gun I took it as an opportunity to take apart and modify with abandon. I'll see how it turns out.


    At this point I only need to get one new seal/ring. It's the one on the piston that has a flange. A kit from a LDS is $25 but I'd rather not buy it since I only need the one ring. Does anyone know where I can get it?

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