SPEARFISHING TIPS

– by Rob Allen

Aiming a speargun differs from person to person. Many old divers have had a problem trying to get used to railguns. I put this down to the way they were used to aiming the old non-rail type gun. A common method is to look at the tip of the spear, put this on the spot you want to aim at and then lift the handle up. As the tip disappears from sight, pull the trigger.

With the railgun having a shorter spear, if you try the same thing, the tip will disappear sooner behind the muzzle, as the spear is shorter. Therefore the handle would not have been raised enough and you now shoot over the target. Some compensate by fitting a longer spear but this affects the speed of the spear. The original railgun was designed to take even shorter spears than are now fitted. Customers did not like the spears that short. Too radical a change from what they were used to, but they do shoot fine. If an older diver used a completely instinctive method of shooting with no sighting at all there is no problem to convert between guns. Shooting at reef fish usually requires either instinctive or “point and tilt” aiming because there is often less time to prepare for the shot.

I have mainly hunted gamefish and before the advent of railguns I used to aim along the side of the gun, sometimes even turning the gun onto its side. (You can’t do this with a railgun as the spear tips out the rail.) By aiming while looking along the side of the barrel you control the vertical axis better than the lateral. With game fish being long and thin, the vertical plane is obviously much more important than the lateral. When old guys had problems aiming the rail gun, I tried to get them to use this method but most would not change.

I needed to get into a pool and just shoot at a target. I needed to see just where the spear goes and what aiming method is best for pool and the ocean. In a pool with the pumps off, no disturbance you can tell exactly where the spear is going, as there are no other influences such as current, swell, moving target etc. To be able to do ongoing pool tests I built a large pool at home with sufficient length to shoot long guns. I soon picked up a few quirks. The main finding was just how much recoil affects the shot and, just how easy it is to adjust the flight of the spear by tweaking the barb.  Another major factor was just how important a straight spear is. A very slight bent in the tip will set the spear off target a long way. This very small bend is almost impossible to see but can be detected when rolling the spear on two edges with the line disconnected and the barb taped up.

Rubber power was a big influence. I found that if the gun was powered up, the recoil caused the gun to shoot left or right, not so much up or down as one would think as with a handgun. How much deflection and which way was relative to how tight I held the gun, how stiff my arm was, which hand I held the gun in and, the power of the rubbers. I am left-handed and the recoil deflection for me is to the right. If I hold the gun handle with my right hand, it deflects to the left. I put this down to the way the handle kicks back into the thumb and then rotates the wrist.

With a 1,3m gun with double 16mm rubbers, set up with a 7,5mm spear, rubbers a little shorter than normal, the left or right deflection is as much as 100mm at max range. My definition of max range is the range a spear will travel and just come out the other side of a good fish. I set up the target such that the spear tip will only go through it and protrude out the other side by about 300mm once stopped by the shooting line. (Single wrap) This 100mm deflection is with a normal grasp of the handle. It improves to about 50mm with a tight grip and stiff-arm but is 150 to 200mm with a slack grip. My personal game fish guns are 1,3m with normal double 16mm rubbers and a 7mm spear. With this set up the lateral deflection at max range is only about 30mm with a normal grip. This is nothing at max range on a good size fish.

Have you ever missed a fish at close range? This happens from time to time, you think it is an easy shot but then you miss totally. I put this down to the recoil. The shot was a dead cert so you just relax and pull the trigger. In this “relaxed” state the gun recoils so much more and… you miss.

To get the vertical accuracy right, I always sight the same way and adjust the barb accordingly. The trailing edge of the barb can be tweaked to raise or lower the spears flight. We used to bend the trailing edge of the barb out a little to help toggle on a fish. This was fine with spears made from 1840MPa steel that was more flexible. With the new 2100Mpa steel we now use, when shot, the spear would hit high with that barb setup like this so we stopped doing it. In the pool I found that a half mm (0,5mm) outward bend of the trailing edge of the barb would lift the spear on my 1,3m gun at max range by as much as 50mm to 70mm.

The way I now aim is to look over the top of my gun. You can’t use the top edge of the handle to line up with as the rubbers sit higher than this. For me to sight properly, (using sighting points like a rifle) I look over the top of the gun and line up the rear rubbers with the muzzle (when loaded). When loaded the rubber creates a “V” like image between them. This is the “V” between the two diameters when looked at end on. The normal closed muzzle I line up such that the middle muzzle hole, the one the spear goes through, sits on this V as you would when sighting a rifle. If you try this and it still shoots high, lower the hole into the “V” more.

I practice sighting like this often so it feels natural when I go into the ocean. If you don’t, it will feel strange. In the pool you will need to take many shots for it to feel right, it does get tiring loading and reloading 20 to 25 times in a row, but it is necessary. Make sure you are wearing a good loading pad. I also always set my shooting line the same way and always set the line to the same side of the spear. Once loaded I also pull the shooting line out from under the rubbers as this helps prevent muzzle wrap. It is a good idea to get into a routine like this. I always try to pool test every new rubber and or spear I fit to my gun before going on a trip. This also gets my eye in, very important before a trip. It costs a lot to go on a trip in terms of time and money; you don’t need to spend the first few days getting your eye in or second-guessing your aiming technique. You might miss that one good fish – it’s just not worth it.

I now use an open muzzle that makes it even easier for me to aim as I can see passed the muzzle, right to the end of the spear. With open muzzles I sight with the edges of the barb that I see when looking down the spear. I just “rest” these on the “V” of the rubbers at the back. The open muzzle is a little more difficult to load the spear line but once used a few times it becomes easier. When changing to an open muzzle it is a good idea to first pool test so you can get familiar with the spear loading and line wrap. It is not a good idea to try this in the ocean while there are fish about.

Point of interest, I have had several novices in my pool who had never shot a spear gun before. I load, hand it to them, then only tell them to keep their arm out straight, hold the handle tight and shoot, all shoot almost spot on. This shows that the way “old divers” aim is the problem, not necessarily the gun.

– by Rob Allen

How do you tell if your spear is straight? Many do not realise just how important a straight spear is, or, how easy it is to check. A slight bend, not detectable by the eye can mean many missed fish and a very frustrating dive. It is always a good idea to regularly test your spear before you dive. It is just as important to test new spears as well as a spear on a new gun.

The best method to test this is to roll the spear. To do this properly you first need to balance the spear. This can be done by cutting the shooting line off or, coiling it up and taping in onto the spear as in the picture below.

The barb also needs to be taped closed because, if the line is loose and the barb open, a straight spear will not roll at all. Once taped up, the spear needs to be rolled on two straight edges. For this, two chairs with straight top edges on the back (top) will work if set up back to back. You can use two speargun barrels or anything suitable with a straight edge, as long as you have two parallel and level edges for the spear to lie on. The distance between the chairs or the straight edges is relative to the spear length. Both edges should be just a little more than half the spear length apart and set level and parallel to each other.

Lay the spear on top of the straight edges at 90 degrees to the surfaces with as much of the spear point end protruding over the one edge. Now roll the spear by using only a finger, putting as little downward pressure as possible, preferably over the straight edge furthest from the spear point.

While rolling, watch the spear point. It should have as little wobble as possible. The more it wobbles the more it is bent. If the spear has difficulty in rolling then it could be very bent. This bend can be caused by a previous fish or, a gun that was mishandled, stood on, poorly transported etc. It is also possible that it could also have been bent from new. It is also possible the original manufacturer was not vigilant enough when straightening the steel or was not aware the supplier had supplied steel that was not top quality.

– by Rob Allen

Rob Allen’s slip tubes are designed to shoot small groupings in the area where the average person would instinctively point. This is only the first half of the equation – the human factor is as important.  We have found normal slip tips are rarely accurate as the tip normally has a little play. This, being right at the tip is where is has the most adverse effect. With the slip tube, the spear becomes the point, greatly improving the control of the spear.

Other factors that can cause inaccuracies come from the gun itself. What will change the point of aim and grouping is the stiffness of the barrel (obviously predetermined), the tightness of the mechanism fixing in the barrel, the stiffness of the mechanism (trigger pull), mass of spear and gun, length and straightness of the spear, and the tension in the band or bands (with the slip tube it is better to increase the rubber load a little as there is more drag from the cable and crimps). The accuracy can also vary pending which hand the gun is held in.

The main factors from the users point of view that will affect the way the gun will shoot, are your basic athletic abilities, the strength of your shooting arm, the way you grip the gun and, how you aim (sight). You might be lucky and your own make-up will complement the setup of a gun you buy. It is always best to spend a little time target shooting in a pool to develop an awareness of the way you shoot and perhaps some minor tweaking of the gun will result in a big improvement in your accuracy.

When shooting and or testing a gun with a slip tip, always hold the gun out with the arm extended and as stiff as possible. Make sure you always wrap the line the same way each time to maintain consistency. It is very important to set the tube up such that all the cable is on top of the tube (see picture) Set the cable up with the trailing section tucked into the middle muzzle hole (with the spear). If you are using an open muzzle, trap the cable under the mono when wrapping it around the spear. The best method to adjust where the gun shoots in the vertical plane is by the two trailing barbs on the slip tip. These trailing edges can be bent up or down depending where you need the shot placed. This edge acts like a small aerofoil. An adjustment of about 1/2mm on the barbs trailing edge will make about a 50mm change at max range compared to before the adjustment. It is good to test your gun and adjust accordingly each time you change the spear and or the rubbers. If the spear shoots low, flatten the top trailing barb a little and open the bottom one a little then test. The reverse is true if it shoots high.

Your spear placement will change over time, as the rubbers get old. When you replace the old rubbers there will be a variance from the old to the new. The tighter the rubber the quicker the spear will get to the target and therefore the less the drop due to the arc of trajectory.  Rubbers also vary a little from make and from batch to batch. To recap, if a gun with a slip tube shoots high, flatten the barb underneath and open out the top barb a little, if it shoots low, do the opposite.

There will also be a slight left to right deflection pending how strong the gun is set up and how tight you hold the handle. This will be more evident with the slip tube. Also, if the gun is over powered this will be much more noticeable, this is due to the recoil. What happens is that the recoil causes the mechanism to rotate in your hand just a little but enough to deflect the spear. A right-handed person will find the gun shooting a little to the left while a left-handed person to the right.

NB: Very important! Do not leave the tube on the spear when not in use as the dissimilar metals will cause corrosion. Keep lubricated when in use.