Speargun Reality Check #1
Comparing Speargun Specifications

Through the years I have read numerous articles and had many conversations with the major speargun manufacturers as well as many “garage gun” makers. Not all, but many, speargun makers make claims like their particular “brand” of speargun shoots further and is more accurate than the other guys. These claims surprise me considering how much more accurate can a speargun be if all of them hit the target dead-on, or, how much further can a speargun shoot because of the brand name attached to the gun? Are these claims false? Or is it a form of advertisement to promote their name and products? Or is there misuse of the words, descriptions and terms used by many speargun makers as well as misunderstandings and misinterpretations by us spearfishermen? Maybe it’s a little of all the above and more?

I recently spoke with a “reputable” major manufacturer of Spearfishing equipment. He was trying to explain to me that, the muzzle-speed of his spearguns was far superior to that of another top name brand after a “test” he had done in a swimming pool.

The Q & A for this particular gun manufacturer is not meant to single out anyone or brand in particular due to the fact these misnomers are commonplace in the industry of Freediving and Spearfishing. Since much of ones ability to Freedive and Spearfish is based on each individual, there is plenty of room for interpretation and therefore many of what is considered rules, laws, facts, training methods, appropriate gear and rigging etc. should be looked at as mere guidelines rather than “law.” Once again, my desire by exposing these claims is simply to encourage anyone who cares to know facts, to question everything around you, force everyone to prove what “facts” they claim.

As stated earlier, many gun makers claim their fame by throwing things they call “facts, proven through tests,” out to all of us so we buy their products or so they simply sound like they know what they are talking about. Claims like “better range” or “better accuracy” or, in this case “better muzzle speed,” due to a particular brand, style of equipment or gun rigging technique. So, I asked this particular speargun manufacturer a series of questions hoping to expose some of the misnomers. It sounded like this:

1. Q. What was the length of the band-stretch of his gun?

   A. His answer, “35 inches.”

2. Q. Next, I asked him what was the length of the band-stretch of the other gun?

   A. His answer, “45 inches.”

3. Q. Third question I asked him was what was the diameter of the spear shaft on his gun?

   A. His answer, “9/32.”

4. Q. Fourth question I asked was what was the diameter of the shaft on the other gun?

   A. He said, “5/16.”

5. Q. Next I asked him what was the diameter of the rubber bands on his gun?

   A. He responded, “5/8.”

6. Q. Next I asked what was the diameter of the rubber bands on the other gun?

   A. He replied, “9/16.”

7. Q. Coming to the end I asked, was the brand of rubber the same for both brands of guns?

   A. He said, “No.”

8. Q. Finishing up, I asked about the shooting line, what type of shooting line did he have on his 9/32 shaft?

   A. He said, “200 lb. Mono.”

9. Q. Lastly, I asked what type of shooting line did the other have on the 5/16 shaft?

   A. He replied, “300 lb. Mono.”

Ok, now down to the nitty-gritty…

1. Q. What was the length of the band-stretch of his gun?

   A. His answer, “35 inches.”

2. Q. Next, I asked him what was the length of the band-stretch of the other gun?

   A. His answer, “45 inches.”

The term "band-stretch" is a measured length based on the distance of the rubber at rest to the rubber pulled back to the loaded position. To explain the relevance of band stretch I will use a law of physics that states something like, "the longer an object is in motion, the longer it will stay in motion." Translation, the more band-stretch a speargun has, the greater distance the spear shaft will travel.

Example A: The following two guns are using the same ratio of products. The only notable difference is the length of the barrel i.e. band-stretch.

• A 48 inch gun with 9/32 x 50 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 20” rubber bands – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about ten (10) feet.
• A 60 inch gun with 9/32 x 65 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 26” rubber bands – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about fifteen (15) feet.

A difference of five (5) feet in overall distance/range is simply due to the increase in length/band-stretch between the two spearguns. The muzzle-speed is the same. The quality of the gun is the same.

3. Q. Third question I asked him was what was the diameter of the spear shaft on his gun?

   A. His answer, “9/32.”

4. Q. Fourth question I asked was what was the diameter of the shaft on the other gun?

   A. He said, “5/16.”

Another law of physics is worded something like, “the heavier an object is in motion the more likely it will stay in motion.” You physics whizzes are laughing at me I know it…anyway… Based on the weight of the 5/16” diameter shaft over the 9/32” diameter shaft and the law of physics mentioned, the 5/16” diameter shaft should travel further. However, an increased ratio of band strength is required to propel the heavier 5/16” diameter shaft; this is where most of the misunderstandings and misinterpretations come from… Due to what I was told for this “test”, “the muzzle-speed was greater on the speargun with the 9/32” diameter shaft,” I know the power-ratio used to push the two shafts was different. Simple trial-and-error and common logic will show that one can increase the muzzle-speed of the heavier spear shaft by increasing the band strength. Again, simple trial-and-error and the laws of physics will prove that when an appropriate amount of power is added to the heavier 5/16” diameter spear shaft it will not only have the same muzzle-speed but it will have greater range.

Example B1:

• A 48 inch gun with 9/32 x 50 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 20” rubber bands – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about ten (10) feet.
• A 48 inch gun with 5/16 x 50 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 20” rubber bands – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about eight (8) feet.

A difference of minus two (-2) feet in overall distance/range is simply due to the increase in weight between the 9/32” diameter shaft and a 5/16” diameter shaft without changing/increasing the rubber strength. Therefore, the muzzle speed would be drastically slower for the 5/16” shaft BUT the quality of the gun stayed the same.

However…

Example B2:

• A 48 inch gun with 9/32 x 50 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 20” rubber bands – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about ten (10) feet.
• A 48 inch gun with 5/16 x 50 inch Hawaiian Shaft, two wraps of 300lb. Mono and (2) 5/8 x 20” rubber bands and one (1) 9/16x20” diameter rubber band – will have an approx. accurate range, measured from the tip of the loaded spear tip, fired horizontally, of about twelve (12) feet.

A difference of plus two (+2) feet in overall distance/range is simply due to the increase in weight between the 9/32” diameter shaft and a 5/16” diameter shaft and an appropriate minimal increase of band strength. The muzzle speed would be, roughly, the same. The quality of the gun still stayed the same.

5. Q. Next I asked him what was the diameter of the rubber bands on his gun?

   A. He responded, “5/8.”

6. Q. Next I asked what was the diameter of the rubber bands on the other gun?

   A. He replied, “9/16.”

Now, this example goes directly against all laws of physics and common sense. Think of it like this… If you have a Big-Block V-8 motor (let the V-8 be the equivalent to 5/8” bands) with 500 horsepower in a huge 4x4 truck (let the truck be the equivalent of a 5/16” spear shaft) and a VW Bug (let the VW Bug be the equivalent of a 9/32” spear shaft) with a standard VW motor (let the standard VW motor be the equivalent to 9/16” bands), what do you think happen if you swapped the motors in these vehicles i.e. a huge 4x4 with a stock VW motor and a VW with a 500 horsepower V-8 motor? Which vehicle do you think would win in a drag race? Now, taking the speargun set up literally and you have a 9/32 shaft with 5/8” dia. bands and a 5/16 shaft with 9/16” dia. bands, which one do you think will fire with a higher muzzle-velocity? DUH!!! to both questions… I hope the answers are obvious to all yall… I don’t think there is any more explanation necessary.

7. Q. Coming to the end I asked, was the brand of rubber the same for both brands of guns?

   A. He said, “No.”

Now, we just covered the subject of rubber diameter and how “obvious” it should be to anyone and everyone that thicker/stronger rubber will have more power than thinner/weaker rubber. But something that is NOT understood by many/most people is the difference in strength and longevity of each BRAND of rubber. Of the colors/brands/styles I’m aware of at this time, there are Green (usually referred to as “Mean-Green”), Solid Black Euro Rubber, Solid Amber Euro rubber, Solid Amber and Solid Black High Modulus (usually referred to as “Gorilla rubber”), Red Ultraviolet coated, Black Ultraviolet coated, Blue Ultraviolet coated and transparent Amber rubber. AND, out of the nine (9) rubber colors/brands/styles mentioned, each and everyone of them can significantly vary in strength with each and every batch due to the fact that rubber is a natural product, it is derived from trees, and is subject to varying quality/strength/longevity standards just like, for example, fruit. Some colors/brands/styles have been “injected” or added synthetic materials into the rubber compound to extend the life of the natural product or the strength, which change the properties of the rubber and may cause a positive or negative effect on the rubber and therefore for each individual diver. With ALL these variables one MUST use the same brand, from the same batch etc. of rubber for accurate testing of equipment. Remember, limiting variables is the KEY to accurate testing results. The fact that this manufacturer used different brands of rubber is yet another reason the results of his “test” will be inaccurate.

8. Q. Finishing up, I asked about the shooting line, what type of shooting line did he have on his 9/32 shaft?

   A. He said, “200 lb. Mono.”

9. Q. Lastly, I asked what type of shooting line did the other have on the 5/16 shaft?

   A. He replied, “300 lb. Mono.”

You might never guess but it is amazing how much of a difference the type and diameter of a speargun's shooting line makes in the shafts overall range, as drastic as several FEET, not inches, or, “I think it made a difference.” For an extreme example, try shooting your speargun without any line… Than put some line twice as heavy as you normally would use. Do your own test and you’ll see very clearly what I’m talking about. And as far as the test in this article…let me sum it all up for all yall…

This article started with a particular spearfishing equipment manufacturer conducting a “test” between two spearguns and coming up with results favoring his product(s). If I asked you to tell me which apple tastes better and I handed you one apple and one orange, there could only be one truly correct answer; only the apple tastes like an apple so the orange could only be the looser…Doesn’t make sense to you??? Try this; you have to have two of the same thing to be able to compare them to each other.

The term muzzle-speed, which is common in the firearms industry, still has a role in the spearfishing industry due to a gun, of sorts, firing a projectile. However, muzzle-speed is only one of many aspects to rate a spearguns “quality” and “effectiveness,” as in firearms as well. The largest factor to consider when deciding which speargun is right for you is the fish you’ll be hunting. The second aspect to consider are the conditions you will be hunting the fish of your choice in… Down the pondering road will be cost and even further down will be ALL the available options, set-ups, versatility, muzzle-speed, etc. for the speargun you are considering. Most spearguns will accept at least a few modifications/upgrades so the muzzle-speed will change with each and every set-up.

A spearguns “accuracy,” is another misused and/or misunderstood word/term. Taking the use of the word literally and logically, when something is accurate, it’s accurate. It can’t be “more accurate.” It’s like saying someone is more dead because he died from being shot by a gun rather than by dying in a car accident… It doesn’t make any sense because when a person is dead, they’re dead. Well, as long as the barrel, spear shaft and the barb(s)/tip of the speargun is straight then the speargun should be “accurate.” But, accurate up to what range(?) is the correct wording to be used to ask questions or to answer questions relating to accuracy and range. Hence, if inaccuracies are the real issue than one must look at the structure and trueness of each particular piece of equipment. Therefore, if a speargun is truly “inaccurate,” there is something bent or broken that shouldn’t be.

Now, the range of a speargun can vary depending on numerous factors. But, and that’s a big BUT(!), by limiting variables for the purpose of accurate test results, it is the laws of physics that ultimately determine a spearguns true RANGE, not the brand. The weight and shape of the projectile, the power projecting it, the density of the medium it is traveling through (in this case, water) as well as some “lesser important” factors like shooting line used to attach the shaft to the gun, crimps etc. The point is, no matter whose name is on what, as long as the same peripherals are used to test with, the test results will be the same!!!

So, am I saying all spearguns are the same? No, not at all! The quality of a speargun cannot be measured merely buy an assumed muzzle-speed of a particular set-up; that would be like saying the quality of a car can be judged merely by the tires it has. There are dozens or even hundreds of factors when considering which brand and model of speargun (and a car) to purchase i.e. (in no particular order) price, weight, maneuverability, availability, durability, ergonomic feel, reputation of quality, product representation and warranties, construction and materials used, looks and personal appeal, resale value, ability to modify, available upgrades, versatility, ease of use, etc… What I am trying to say is, don’t let someone pull the blinds over your eyes with things they call “facts” or good advertising… Question everything… including all of what I mentioned in this article.