Armament of spearguns and technical characteristics:
the standard armament of this speargun is four elastomers engines from 16 mm diameter branches Primeline with percent elongation of 320.

The M.S. 4 is braced with four passes of terminal nylon wrapped between the line-releaser and the pass-line placed below the stem ,first of the pulleys. The terminal is approximately 8 meters long that the end of the shot is played everything from the auction! The useful range of this the spear, therefore, is more than 7 meters.
The M.S. 4 launches shaft 8 mm diameter 150 cm long weighing about 560 grams about.

It comes standard with the new release mechanism roller and the reel with roll diameter 100 mm.
In this speaguns was applied a new line-releaser bigger, derived from the previous model used on Saber series, because it must be able to hook up 4 past of the end of nylon also has changed the bracket applied on the head of my spearguns with function to hold the rod with an O-ring or with a round of nylon terminal; the new solution which will be standard for all other models Saber, in fact, is a spout shaped steel AISI 316 drowned in the resin in the final part of the guide-rod secured by a screw perpendicular to the guide.

As in the Mega Saber with three elastic, the rod it reaches a top speed of over 30 m / sec.

Box on mass factor
I wanted to design a speargun for catching large pelagic that stood out from traditional spearguns for , whose wooden casks weigh about five pounds, and the , lighter, with the frame aluminum tube, or carbon composite. The inertial mass is modest enough to make it difficult for the angler underwater control a recoil. The weight of the trunk of the M.S. 4 is around 2.5 Kg.

If we compare:

the weight of the stem (of the speargun without elastics), and the weight of the rod and more a third of the weight of the four elastic (1/3 x 4 x 120 gr, part of the elastomers that is projected forward at the speed of the rod).
We obtain a technical data: the value that I think is very interesting and appropriate to define this category of the speargun.
The mass factor, in fact, is the ratio of the masses that accelerate in the direction of the shot and those that recoil in the opposite direction.
It is legitimate to ask how and why I rated the factor of mass ratio: When the rod is thrown forward by the elastic, for a very well known physical law, at the same time, the speargun moves back with a speed which in first approximation complies with the law of conservation of the momentum of the components of speargun in motion.
Neglecting, in this phase of the study, the resistors fluid and the resistance opposed by the fisherman with his hand (by analyzing only the before and after a shot), the recoil velocity is determined by the equation:

mass + mass 1/3 of the elastic rod and bow x speed shaft
mass of speargun (without elastic and rod) x recoil velocity of the stem

Since the first part of the equation offers known values, once experimentally measured the speed of the shaft, the speed of the gun recoil not challenged depends on the mass of the rifle without elastic. During the design, this virtual speed of the speargun recoil c

alculated without taking into account the resistance opposed by the fisherman is an important term in the evaluation of the characteristics of a the speargun because informs us about the extent of that the fisherman will counteract with the arm and with the body.
The rifle, however, under field conditions, is challenged by the fisherman...

At the first examination, where it analyzes the rifle not bound to follow a second analysis which take into account the actual situation. I propose this method of investigation very intuitive: If the equation of the quantity

 of motion indicated above instead only the mass of the rifle's add a part of the mass of the fisherman, here is that the recoil velocity is dramatically reduced.
This happens if the recoiling mass of the stem are in addition to that of the hand, arm and part of the body in the condition that the fisherman, in carrying out the shot is disposed in axis with the gun, namely, the longitudinal axis of his body is parallel or in line with the axis of the stem of the rifle. The subjective component, therefore, may change, the use, the technical characteristics of a gun! This explains how the great fishermen will achieve important catches with the (rifles with modest inertial masses). Paradoxically, it is the beginner who has more need of a good rifle, I mean a factor of the speargun with a mass greater than the value <3>.

Sometimes, however, even the fisherman good standard fails in this endeavor.

For example:
in the case of a shot of shouldering side, when the axis of the body is inclined to the axis of the stem recoil, in this case, the additional mass of the recoil braking will be little more than the mass of the forearm. As it happens in the shot from the surface from top to bottom.
And in the shot with the , classic shot of the fisherman unconcentrated not stiff arm at the time of pulling the index finger on the trigger, which is common in cases of prey that appear suddenly in front of the fisherman. In conclusion, the stem of the speargun must have an inertial mass which also takes account of situations of shot is not optimal because you should not rely only on good shooting technique of the fisherman. Designing guns with masses of stem redundant, that could solve the problem of the recoil, however, creates difficulties in managing tool equally serious gun maneuverability, speed of both lateral and vertical tilt. Defects, in the shooting placed in spear fishing and falling be considered negligible, but that fishing ambush, the dynamic aspect represent a insurmountable limit. Here the clear purpose of the project M.S. 4: Hold a speargun from a without having to manage a which requires muscle strength relevant to every move.

The idea that I have done in recent years, both as a fisherman and as a design engineer is that the rifles for underwater fishing prevails a fundamental problem: Counteract the recoil of the gun!
The recoil patterns Jedi that I could study in 2004 with the filming of the shot in the tank made with a camcorder to 1000 ftgr / sec was a phenomenon that lasted an average of thirty milliseconds, which means that in a few hundredths of a second are discharged on hand sixty-plus kg weight.
A dent that could not always be well controlled by the fisherman! In the following years, until today, with the
and , I tried to break the launch rod in two stages with distinct acceleration: the first due to the more rigid part of the propulsion system (chargers potentiator and metal spring bow thruster), the second due to the elastic , real engine of speargun. In essence, with the transient starting place from the more rigid, and the actual launch performed from the strap that rests on the pulley. In doing so, in the first part of the launch of the rod generates a secondary recoil of low intensity seen the low average speed at which it develops (the rod from a standstill comes to approximately one third of its maximum speed), and subsequently a recoil primary, much more intense but develops after the secondary (two accelerations in different times and different) .In this way is recoil in two stages that are easier to handle for spearfishing (see clip shooting with the enhancer on You Tube channel company Dapiran).

It is natural to ask why this model is not very powerful, I expected the armament with the Potentiator or the Bow mover that would have further strengthened the shot without exasperating the recoil. The speed and range of the rod with the armament of the four classic circular bands have proved more than enough and I do not want to force the potential client to adopt solutions that, at present, is poorly understood. I do not exclude, however, that those who buy the speargun that can adopt a alternative weapons with the use of the Potentiator or the Bow mover, as was the case on the part of many customers for the Mega Saber three circular bands. Box on the moment of recoil or tipping In the design of the M.S. 4 there has been a substantial change in the shape of the stem than the standard models Saber.

I figured the arrangement of pulleys and the size of the section of the stem so that it annuls the tipping of the speargun (I censored dramatically part of this box, where I explained in detail the developments and the effects of the new project). The tipping is a phenomenon ballistic particularly negative in the spearguns very powerful since, in the majority of projects, the recoil of the speargun combined with the resistance opposed by the fisherman's hand on the handle, create a
which raises the head of the stem prejudicing the interior ballistics of the rod and the final accuracy of the shot. To be precise the shaft M.S. 4 instead of rearing up during the launch is lowered leaving free the rod along its trajectory without coming into contact with the stem. This phenomenon is visible in the shot that clips are attached to this article: just place a ruler on the PC screen in the trunk before it popped the shot, to shoot successive frames show the stem lower than the position of the ruler!

The operation and behavior in fishing for MS 4 can be seen in two clips of which carry the link below: