Closed vs. Open Speargun Muzzles

[BoltSnap]

Are there any advantages for closed speargun muzzles over open muzzles? All I can discern is that closed muzzles are more of a limiting factor than offering any kind of an advantage. What am I missing and why do gun makers (in Europe mostly) offer closed muzzles?

 

[CuzzA]

You basically have three options. Closed track, open track and closed muzzle.

A closed track will generally be a hair more accurate as the shaft won't flex when shot. The disadvantages are you can't back load and a common problem is when shooting fish at close range where the end of the shaft remains in the gun and the fish is beating away, well, your track is getting beat to hell too. There's one manufacturer I know of addressing this issue for a future gun. You also have to use more expensive shark fin shafts.

An open track gun will use a line wrap to hold the shaft down in the track. The disadvantage is you must use a line and can't freeshaft. Though these guns are rarely used on scuba. They are less accurate than a closed track.

Finally a closed muzzle gun will be the preferred choice on scuba. On most setups they are designed with less expensive notched shafts. They can be back loaded when freeshafting and easily swap over to lineshafting with a slide ring. Not all muzzles are the same, though. For example a Biller only has about an inch of guided muzzle, whereas an Ocean Rhino has around four inches. This makes a difference by straightening out that wobbly shaft-flex-whip as the shaft leaves the open track.

 

[BoltSnap]

Biller only has about an inch of guided muzzle, whereas an Ocean Rhino has around four inches. This makes a difference by straightening out that wobbly shaft-flex-whip as the shaft leaves the open track.

I am not sure that I am following what you said above. What is "guided muzzle"?

You are talking from the prospective of a "scuba" diver who is spearfishing not a free diver I think. In my part of the world, especially in Europe, spearfishing on scuba is a big no no (I don't agree or subscribe to this line of thinking) so not sure if what you said applies universally. The closed muzzles are made and sold in Europe and used by free divers not scuba divers. There must be another reason or benefit to closed muzzles in addition to what you said that applies to free divers. What I dislike the most about closed muzzle guns is that I have to use shafts with notches and a band with metal wishbone. Shafts with shark fins are too big to pass through the muzzle.

 

[CuzzA]

So, there's many variations. I was trying to give you a general overview. Here's generally what's available from the more popular brands and I've included some images to illustrate my previous post. Free diving is just as popular here. We do it all.

Koah Battle Axe. Fully enclosed track. No muzzle.

Riffe. Open track. Aka Euro style. Note the line wrap.

Mako Spearguns. Same deal. Open track. Line wrap.

Red Tide Speargun. Open Track. Line wrap.

A.B. Biller. Open Track. Closed Muzzle.

Ocean Rhino. Open Track. Longer Closed Muzzle.

 

[BoltSnap]

A.B. Biller. Open Track. Closed Muzzle.

This is a "closed" muzzle but isn't there space at the top for the shaft's shark fins to pass through no issue?

Ocean Rhino. Open Track. Longer Closed Muzzle.

This one appears to be completely closed but is the "roof/top" of the enclosure high enough for the shaft's shark fins to pass through?

 

[BoltSnap]

So, there's many variations. I was trying to give you a general overview.

Thank you VERY much!!

 

[CuzzA]

I am not sure that I am following what you said above. What is "guided muzzle"?

You are talking from the prospective of a "scuba" diver who is spearfishing not a free diver I think. In my part of the world, especially in Europe, spearfishing on scuba is a big no no (I don't agree or subscribe to this line of thinking) so not sure if what you said applies universally. The closed muzzles are made and sold in Europe and used by free divers not scuba divers. There must be another reason or benefit to closed muzzles in addition to what you said that applies to free divers. What I dislike the most about closed muzzle guns is that I have to use shafts with notches and a band with metal wishbone. Shafts with shark fins are too big to pass through the muzzle.

I think we're just having a small breakdown in nomenclature. When I think of muzzle, I think business end of gun, but in terms of a speargun I view it as a separate part. When I think track, I think barrel... but of course it's not a barrel. The track is either open, allowing the shaft to lay into it or it's a closed track and the shaft can only be inserted from the front of the gun.

I'll add some more media as this thread may be useful for anyone searching the topic.

Open track. Line Wrap.

Open Track. Closed Muzzle. (This illustrates the new Evolution shaft) Great system.

Closed Track.

 

[BoltSnap]

I wasn't talking about "track," I am talking about the end of the the gun where the bands are attached. Open muzzle is where there is no plastic cover of the end of the gun and "closed" muzzle is where is a "cover" with no need for the line holding the shaft down.

 

[CuzzA]

This is a "closed" muzzle but isn't there space at the top for the shaft's shark fins to pass through no issue?


This one appears to be completely closed but is the "roof/top" of the enclosure high enough for the shaft's shark fins to pass through?

The Biller muzzle could shoot a shark fin shaft if it had the correct notch.

The Rhino will not shoot a shark fin shaft.

Honestly, the biggest difference between a freediving gun and a scuba gun will be the presence of a reel. Then you get into some BIG blue water guns for shooting tuna, wahoo, and billfish. These are likely going to be setup with a float and float line since no human could overpower a fish that size.

And why not throw in a video of my own using my Biller/Rhino Frankenstein gun.

 

[Sam Miller III]

@CuzzA
I commend you for being a very knowledgeable and patient person.
Certainly a well presented explanation of a spear gun and its basic components
Keep up the good work.

​

Now on to Spear Guns Parts 11. 111 1111, 11111 etc
Sam Miller.111

@Marie13 CE