Closed vs. Open Speargun Muzzles

[MAKO Spearguns]

One point of clarification, if a speargun uses a notched shaft, they DO NOT always have to use a solid metal wishbone. IF (this is a big one) the notch itself is carefully constructed and the edges rounded and smoothed out, then a "soft" or dynema wishbone can be used.

Another consideration, scuba divers in certain locations (generally where there is reasonably good visibility) may choose to shoot an untethered shaft (or freeshaft). This has certain benefits (and drawbacks), but generally requires a closed muzzle.

Freedivers pretty much always use a tethered line on their spearguns. There are a variety of reasons, but a simple factor might be that a scuba diver has time to search and hunt down a fish that has swam away with a freeshaft, but a freediver has much less time and returning to the surface may result in losing sight of the fish and shaft and this would be a big negative. In the Bahamas, a lot of freedivers shoot freeshaft from a Hawaiian sling (since guns are not allowed) and the water is often clear.

The question was raised about the potential benefit of a closed muzzle for a freediver. As shown in the pictures above, if the gun has an open track, then the shaft generally has to be "locked down" with a wrap of shooting line when an open muzzle is used. Otherwise, the shaft could rise up from the muzzle when loaded and this would be very undesirable. If a closed muzzle is used on a gun, then the shaft is constrained from moving upward and this eliminates the need to wrap the line over the shaft. Thus, SOME people are of the opinion that a closed muzzle is quicker and easier to load.

Other people, learn to do the line wrap very quickly and efficiently and they feel that an open muzzle gives a better, more clear and unobstructed sighting down the shaft - which presumably enhances aiming.

The benefits and drawbacks of different features are the subject of many spearfishing discussions and personal preference often has a lot of significance in what type of gun a diver uses.

 

[BoltSnap]

Thank you @CuzzA and @MAKO Spearguns for your outstanding contribution, you are most kind and knowledgeable!!

My issue with the closed muzzle guns as I see it (using Euro guns NOT Rhino type of closed muzzles) freediving:

1. Can't fit shafts with shark fins through the closed muzzle at all. (I have tried it small profile shark fins and it is a no go)

2. I have to use notched shaft which means using bands with wire wishbones which I don't like and it appears to be "unsafe". The dynema friendly smooth notched shafts as mentioned by Dano aren't available from any of the vendors I know in Europe.

3. As a "beginner" band gun user, I find no issues with tying down the top of the shaft with line at all so I still see no advantage for the closed muzzle over the open muzzle in terms of not having to tie down the shaft especially considering that you lose the ability to use shafts with shark fins.

4. Bands with metal wishbone appear to be more difficult to make as a DIY than bands with soft dynema wishbone.

5. Other reasons I forget now

(I have questions about freeshafting but I'll leave them to a separate thread )

 

[MAKO Spearguns]

If someone wants to hand make bands using the metal wishbones and use cord to tie the constrictor knots, it is not harder on solid metal wishbones.

In fact, in all honesty, one of the more challenging aspects of making your own bands is insertion of the wishbone bead or stopper. With a hard, solid wishbone, that step is very quick and easy and can be accomplished by hand, but pliers, a rag and a drop of soap to lubricate the hole make it very easy. Insertion will take less than a second.

We offer a special tool that facilitates insertion of a "soft" or dynema line wishbone into the latex tubing. When you have the proper tools, insertion of the soft wishbone is not really difficult either.

 

[CuzzA]

Thank you @CuzzA and @MAKO Spearguns for your outstanding contribution, you are most kind and knowledgeable!!

My issue with the closed muzzle guns as I see it (using Euro guns NOT Rhino type of closed muzzles) freediving:

1. Can't fit shafts with shark fins through the closed muzzle at all. (I have tried it small profile shark fins and it is a no go)

2. I have to use notched shaft which means using bands with wire wishbones which I don't like and it appears to be "unsafe". The dynema friendly smooth notched shafts as mentioned by Dano aren't available from any of the vendors I know in Europe.

3. As a "beginner" band gun user, I find no issues with tying down the top of the shaft with line at all so I still see no advantage for the closed muzzle over the open muzzle in terms of not having to tie down the shaft especially considering that you lose the ability to use shafts with shark fins.

4. Bands with metal wishbone appear to be more difficult to make as a DIY than bands with soft dynema wishbone.

5. Other reasons I forget now

(I have questions about freeshafting but I'll leave them to a separate thread )

There are manufacturers who use the Biller muzzle on their freedive guns to eliminate the need for a line wrap and still use a shark fin shaft. Unfortunately I can't think of their names at the moment.

Nevertheless, perhaps you should build your own gun or have one custom made to your specs.

 

[Akimbo]

4. Bands with metal wishbone appear to be more difficult to make as a DIY than bands with soft dynema wishbone.

The main reason that metal wishbones have lost favor is they can cause a lot of damage when they fail. Both will hurt but Dynema is less likely to tear skin when it breaks.

 

[CuzzA]

Someone has addressed the metal wishbone issue. If you note in my video, the band I'm using is a sample I was given that has a much stronger horseshoe shape. It seems to be working well so far this year. Inevitably with the standard wishbone, our arms naturally want to bend out when loading the gun and that's when they break. I prefer steel cable over dynema on notched shafts because the notch tends to cut the dynema. Of course cable comes with its own set of drawbacks. Tends to twist and if a strand breaks it will scratch your hand.

 

[MAKO Spearguns]

Solid metal wishbones are also prone to snapping when/if the diver uses sloppy technique to unload the band. Cable braided steel wishbones do fray and wear out and can cause painful punctures in the hands, but they are very strong and will undergo a lot of fraying and damaged before they eventually fail.

In other words, steel cable gives the diver a lot of warning before failure. Solid steel wishbones can sustain very small stress cracks that are not easily seen. Thus, they can appear ok, but can sometimes fail without much warning, which can be disappointing and as mentioned above, can injure your hands.

 

[BoltSnap]

The main reason that metal wishbones have lost favor is they can cause a lot of damage when they fail. Both will hurt but Dynema is less likely to tear skin when it breaks.

I know about this and I have seen it first hand, tore skin and flesh from a finger.

 

[BoltSnap]

I prefer steel cable over dynema on notched shafts because the notch tends to cut the dynema. Of course cable comes with its own set of drawbacks. Tends to twist and if a strand breaks it will scratch your hand.

Cable braided steel wishbones do fray and wear out and can cause painful punctures in the hands, but they are very strong and will undergo a lot of fraying and damaged before they eventually fail.

Can these braided steel cable wishbones be covered by a hollow flex tube to protect them and prevent punctures to the fingers and hands yet fit into the notch?

 

[MAKO Spearguns]

That's not really practical. The wire is under tremendous pressure when loaded and in contact with a very small area of the shaft. In addition, if the diver is not super careful when loading symetrically, they may "saw" the wishbone side to side to center it, which is super destructive and would remove a plastic coasting in an instant. the steel cable will last a while and fairs better than dynema, but the real solution is to use shafts that have a rounded notch or rounded fin.

If a diver is using a shorter gun, which does not require grabbing the actual wishbone to load, then some progressive cable fraying is not that troublesome if you keep your hands off it and wear good quality gloves. In other words, for a shorter or medium length gun, if the diver can just reach up and grab the sides of bands after the wishbone they only have to touch the latex band material.