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C4 Graphite Accuracy

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
EXA
Yep and it shouldn’t be there. And there is no easy way of fixing that unless you are going to rebuild it.
EXACTLY. So adding a track would do nothing to this gun to improve the accuracy.
A gun without a track can be just as accurate as a gun with a track, believe it or not. Steve Alexander, an old Long Beach Neptune who invented the Enclosed Track for blue water hunting guns, said so himself. You can search his findings on this site.
There were guys building fully ballasted blue water guns that were extremely accurate in the 80’s with 6 or more bands, but they weighed 20lbs. That’s because if a gun is strait and stable the shaft should rest flat on the surface of the gun between the handle and the muzzle. So if it doesn’t flex why would it be any less accurate? Think about that.

That is not the problem with the Graphite 116. the absence of a semi enclosed track just makes the flex of the tube more obvious in that gun as Hugo can clearly see for himself doing that simple test I described in my first post on this thread.
Clear waters,
 
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As C4 don't seem to come to the party on these matters (another C4 had a sideways distorted section of track and the owner was told that was impossible) you can maybe return it to the vendor and ask for a replacement gun of a different type. You say that the gun has been in your possession for 9 months which would be within the warranty period.
 
From the C4 website.

HOW CAN I CALCULATE THE LENGTH OF THE BANDS FOR THE SPEARGUNS?
A) CALCULATION OF THE LENGTH OF THE BAND FOR SPEARGUNS WITH HEAD:
1 – deduct the length of the steel/dyneema wishbone used from the measurement of the length measured of the head/band elevator to the notch/fixing fin of the shaft (eg. 99cm) (eg. 99 – 5 = 94cm).

2 – divide the result (eg: 94cm) by the stretch factor desired for the chosen band. For the C4 Hi-Speed bands of any diameter, the factor of extension recommended varies between 3.5 and 4.0 (eg: 94 : 3.7 = 25.40cm).

3 – the value achieved (eg: 25.40cm) is the length of a ban measured from one clench to another.




B) CALCULATION OF THE LENGTH OF THE BAND FOR SPEARGUNS WITH LOOP ( CIRCULAR BAND ):
1+2+3 – calculate everything as above for spearguns with muzzle, points 1+2+3.

4 – the length achieved must be multiplied by two (eg: 25,.0 x 2 = 50.80cm) as there are two moving arms.

5 – the measurement of the inactive course of the band should be added to this value (eg: 50.80cm), required to create movement to the muzzle. Due to friction created by the extremely heavy specific pressure created between this section of the band and the surface of the speargun, where they come into contact, mutual sliding cannot occur. This is a portion of the band that remains inactive. This measurement should be added to the length, as indicated in point 4, and it depends on the shape of the head of the speargun, the larger it is, the longer this measurement will be.





For our spearguns with loops, add: Urukay +5,0cm - Joker +4,5cm Graphite +4.0cm (eg: Graphite99 – 50.80 + 4.0 = 54.30cm length of the loop from one constrictor knot to another)

For multi-band spearguns, remember that the measurement of point 1 may vary for each couple or loop according to the notch/fixing fin considered.






WHICH SHAFT AND BAND MEASUREMENTS ARE RECOMMENDED FOR THE C4 SPEARGUNS?
Mr.DARK 119
aste/shafts : 7x1600
BLACKBULL 17,5x300 + 16x270 -- 16x295 + 16x270

Mr.DARK 104
aste/shafts : 7x1400
BLACKBULL 17,5x270 + 16x240 -- 16x270 + 16x240

Mr.DARK 94
aste/shafts : 6,5 x 1300
BLACKBULL 17,5x240 -- 16x240 + 16x220

Mr.DARK 79
aste/shafts : 6,5 x 1150
BLACKBULL 17,5x200 -- 16x190

Mr.DARK 61
aste/shafts : 6,25 x 1000
BLACKBULL 17,5x160 - 16x150

GRAPHITE 132

aste/shafts : 6,75 x 1700 - 7,0 x 1600
BLACKBULL ( circolare lungo/long loop) 17,5x780 - 16x730 - 14x670
BLACKBULL ( circolare corto/short loop ) 17,5x730 - 16x670 - 14x630

GRAPHITE 116
aste/shafts : 6,5 x 1600 - 6,75 x 1600 - 7,0 x 1500
BLACKBULL ( circolare lungo/long loop ) 17,5x700 - 16x660 - 14x630
BLACKBULL ( circolare corto/short loop ) 16x640 - 14x610

GRAPHITE 99
aste/shafts : 6,5 x 1400 - 6,75 x 1300
BLACKBULL ( circolare lungo/long loop ) 17,5x700 - 16x550 - 14x510
BLACKBULL ( circolare corto/short loop ) 16x490 - 14x460

GRAPHITE 83
aste/shafts : 6,25 x 1200 - 6,5 x 1150
BLACKBULL ( circolare lungo/long loop ) 17,5x500 - 16x460 - 14x430
BLACKBULL ( circolare corto/short loop ) 16x410 - 14x380

Mr.Carbon/Mr.Iron 119 PS
aste/shafts : 6,25 x 1600 - 6,5 x 1600 - 6,75 x 1500
BLACKBULL 17,5x290 - 16x280

Mr.Carbon/Mr.Iron 104 PS
aste/shafts : 6,25 x 1500 - 6,5 x 1400 - 6,75 x 1300
BLACKBULL 17,5x270 - 16x260

Mr.Carbon/Mr.Iron 94 PS
aste/shafts : 6,25 x 1300 - 6,5 x 1300
BLACKBULL 17,5x250 - 16x240

Mr.Carbon/Mr.Iron 79 PS
aste/shafts : 6 x 1150 - 6,25 x 1150 - 6,5 x 1100
BLACKBULL 17,5x230 - 16x220

Mr.Carbon/Mr.Iron 61 PS
aste/shafts : 6 x 1000 - 6,25 x 1000
BLACKBULL 16x170 - 14x160

URUKAY 120
aste/shafts : 7,0 x 1700 - 7,5 x 1700 - 8 x 1600
BLACKBULL ( triplo ela/triple bands ) 16x720 + 16x700 + 16x680
BLACKBULL ( doppio ela/double bands ) 17,5x730 + 17,5x700

URUKAY 105
aste/shafts : 7,0 x 1500 - 7,5 x 1500 - 8 x 1400
BLACKBULL ( triplo ela/triple bands ) 16x640 + 16x620 + 16x600
BLACKBULL ( doppio ela/double bands ) 17,5x640 + 17,5x620

URUKAY 90
aste/shafts : 7,0 x 1300 - 7,5 x 1300
BLACKBULL ( triplo ela/triple bands ) 16x540 + 16x510 + 16x480
BLACKBULL ( doppio ela/double bands ) 17,5x540 + 17,5x510
 
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And more on accuracy.
SUGGESTIONS TO IMPROVE PRECISION OF THE C4 SPEARGUNS
Some parameters affect the level of precision of our spearguns. If there is no precision or the level of precision is inadequate, it is always best to check it.

For our spearguns without any kind of bar guide (single shell, Mr.Carbon/MR.Iron up until 2012), the best conditions for precision are achieved using a shaft with traditional notches (no fins) and nose cones with straight drive, like the ones whose coupling occurs through the use of a metal cable or dynema (no nose cones made from shaped/bent steel).

Our spearguns are fitted with a shaft guide (Urukay, Joker) or Shaft Slider (Graphite, Mr.Carbon/Mr Iron series since 2013) and they work in the best possible way with any kind of shaft, while the straight drive nose cones are always recommended.

Correct balancing of any kind of speargun is achieved when, with the gun loaded and with the handle bar laid to rest on an open palm, the tip of the shaft falls downwards at a speed of approximately 3-4 fingers per second (5.7cm). In water this is much easier to check.

For models fitted with an adjustable grip, pay special attention to the type and to the thickness of the mobile element of the grip. Out of the two standard versions provided, the narrower version provides greater aiming precision. Its regulation must be performed making sure that the last phalanges of the index finger rest on the trigger. If it has a regulation with less washers, due to the sensitivity of the trigger, the aim will definitely be less accurate.

It is possible to correct setting of the aim if it is too high/low, by acting on the number of washers of thickness of the grip. For example, if the aim is too high, add one or two washers to the upper screw, vice versa if the aim is low. Here is a link illustrating the regulation possibilities:


impugnatura_anim.gif


Remember that one washer should be removed, passing from summer gloves to winter ones and vice versa. As a general indication, normally a hand that wears L size gloves (span opening of approximately 20-21cm) has an excellent level of regulation with 6 washers with 3mm gloves and 7 washers for light summer gloves.

Obviously, the shaft should be substantially straight. To check this, once it has been detached from the heaving line or nylon and after having blocked the barb with a piece of adhesive tape, it should be rotated vertically on the tip. Any possible pleats or imperfections to the shaft will be clearly visible.
 
They’ll come to the party. They just have to be contacted directly. I will forward this information to them. They don’t monitor Internet forums, they wait for a customer to contact them. Hugo when did you buy this gun? And where? I’ll pass your information on to the owner.
 
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Sell it to him...There is a reason yours is accurate and his isn't and it has to do with production. If you do the same test I mentioned to him I bet yours doesn't flex as much.
With just one band in loading tab I get ligh under spear almost all the way... Wouldn't this make the gun inaccurate but precise (missing same way all the time)? You obvislouly dealt with more graphites than me but I've seen how an unbalanced graphite 83 didn't produce good results. Once it was rebalanced by C4 it is now shooting great. Have you seen pictures with graphites and MR carbon/iron with added lead in the front?
 
Last edited:
From the C4 website.

HOW CAN I CALCULATE THE LENGTH OF THE BANDS FOR THE SPEARGUNS?
A) CALCULATION OF THE LENGTH OF THE BAND FOR SPEARGUNS WITH HEAD:
1 – deduct the length of the steel/dyneema wishbone used from the measurement of the length measured of the head/band elevator to the notch/fixing fin of the shaft (eg. 99cm) (eg. 99 – 5 = 94cm).

2 – divide the result (eg: 94cm) by the stretch factor desired for the chosen band. For the C4 Hi-Speed bands of any diameter, the factor of extension recommended varies between 3.5 and 4.0 (eg: 94 : 3.7 = 25.40cm).

3 – the value achieved (eg: 25.40cm) is the length of a ban measured from one clench to another.




B) CALCULATION OF THE LENGTH OF THE BAND FOR SPEARGUNS WITH LOOP ( CIRCULAR BAND ):
1+2+3 – calculate everything as above for spearguns with muzzle, points 1+2+3.

4 – the length achieved must be multiplied by two (eg: 25,.0 x 2 = 50.80cm) as there are two moving arms.

5 – the measurement of the inactive course of the band should be added to this value (eg: 50.80cm), required to create movement to the muzzle. Due to friction created by the extremely heavy specific pressure created between this section of the band and the surface of the speargun, where they come into contact, mutual sliding cannot occur. This is a portion of the band that remains inactive. This measurement should be added to the length, as indicated in point 4, and it depends on the shape of the head of the speargun, the larger it is, the longer this measurement will be.





For our spearguns with loops, add: Urukay +5,0cm - Joker +4,5cm Graphite +4.0cm (eg: Graphite99 – 50.80 + 4.0 = 54.30cm length of the loop from one constrictor knot to another)

For multi-band spearguns, remember that the measurement of point 1 may vary for each couple or loop according to the notch/fixing fin considered.






WHICH SHAFT AND BAND MEASUREMENTS ARE RECOMMENDED FOR THE C4 SPEARGUNS?
Mr.DARK 119
aste/shafts : 7x1600
BLACKBULL 17,5x300 + 16x270 -- 16x295 + 16x270

Mr.DARK 104
aste/shafts : 7x1400
BLACKBULL 17,5x270 + 16x240 -- 16x270 + 16x240

Mr.DARK 94
aste/shafts : 6,5 x 1300
BLACKBULL 17,5x240 -- 16x240 + 16x220

Mr.DARK 79
aste/shafts : 6,5 x 1150
BLACKBULL 17,5x200 -- 16x190

Mr.DARK 61
aste/shafts : 6,25 x 1000
BLACKBULL 17,5x160 - 16x150

GRAPHITE 132

aste/shafts : 6,75 x 1700 - 7,0 x 1600
BLACKBULL ( circolare lungo/long loop) 17,5x780 - 16x730 - 14x670
BLACKBULL ( circolare corto/short loop ) 17,5x730 - 16x670 - 14x630

GRAPHITE 116
aste/shafts : 6,5 x 1600 - 6,75 x 1600 - 7,0 x 1500
BLACKBULL ( circolare lungo/long loop ) 17,5x700 - 16x660 - 14x630
BLACKBULL ( circolare corto/short loop ) 16x640 - 14x610

GRAPHITE 99
aste/shafts : 6,5 x 1400 - 6,75 x 1300
BLACKBULL ( circolare lungo/long loop ) 17,5x700 - 16x550 - 14x510
BLACKBULL ( circolare corto/short loop ) 16x490 - 14x460

GRAPHITE 83
aste/shafts : 6,25 x 1200 - 6,5 x 1150
BLACKBULL ( circolare lungo/long loop ) 17,5x500 - 16x460 - 14x430
BLACKBULL ( circolare corto/short loop ) 16x410 - 14x380

Mr.Carbon/Mr.Iron 119 PS
aste/shafts : 6,25 x 1600 - 6,5 x 1600 - 6,75 x 1500
BLACKBULL 17,5x290 - 16x280

Mr.Carbon/Mr.Iron 104 PS
aste/shafts : 6,25 x 1500 - 6,5 x 1400 - 6,75 x 1300
BLACKBULL 17,5x270 - 16x260

Mr.Carbon/Mr.Iron 94 PS
aste/shafts : 6,25 x 1300 - 6,5 x 1300
BLACKBULL 17,5x250 - 16x240

Mr.Carbon/Mr.Iron 79 PS
aste/shafts : 6 x 1150 - 6,25 x 1150 - 6,5 x 1100
BLACKBULL 17,5x230 - 16x220

Mr.Carbon/Mr.Iron 61 PS
aste/shafts : 6 x 1000 - 6,25 x 1000
BLACKBULL 16x170 - 14x160

URUKAY 120
aste/shafts : 7,0 x 1700 - 7,5 x 1700 - 8 x 1600
BLACKBULL ( triplo ela/triple bands ) 16x720 + 16x700 + 16x680
BLACKBULL ( doppio ela/double bands ) 17,5x730 + 17,5x700

URUKAY 105
aste/shafts : 7,0 x 1500 - 7,5 x 1500 - 8 x 1400
BLACKBULL ( triplo ela/triple bands ) 16x640 + 16x620 + 16x600
BLACKBULL ( doppio ela/double bands ) 17,5x640 + 17,5x620

URUKAY 90
aste/shafts : 7,0 x 1300 - 7,5 x 1300
BLACKBULL ( triplo ela/triple bands ) 16x540 + 16x510 + 16x480
BLACKBULL ( doppio ela/double bands ) 17,5x540 + 17,5x510


This is what I followed for my rubber's length
2x 14 mm
 
They’ll come to the party. They just have to be contacted directly. I will forward this information to them. They don’t monitor Internet forums, they wait for a customer to contact them. Hugo when did you buy this gun? And where? I’ll pass your information on to the owner.

Adreno Spearfishing, Brisbane
Guarantee Number F085.1935
 
And more on accuracy.
SUGGESTIONS TO IMPROVE PRECISION OF THE C4 SPEARGUNS
Some parameters affect the level of precision of our spearguns. If there is no precision or the level of precision is inadequate, it is always best to check it.

For our spearguns without any kind of bar guide (single shell, Mr.Carbon/MR.Iron up until 2012), the best conditions for precision are achieved using a shaft with traditional notches (no fins) and nose cones with straight drive, like the ones whose coupling occurs through the use of a metal cable or dynema (no nose cones made from shaped/bent steel).

Our spearguns are fitted with a shaft guide (Urukay, Joker) or Shaft Slider (Graphite, Mr.Carbon/Mr Iron series since 2013) and they work in the best possible way with any kind of shaft, while the straight drive nose cones are always recommended.

Correct balancing of any kind of speargun is achieved when, with the gun loaded and with the handle bar laid to rest on an open palm, the tip of the shaft falls downwards at a speed of approximately 3-4 fingers per second (5.7cm). In water this is much easier to check.

For models fitted with an adjustable grip, pay special attention to the type and to the thickness of the mobile element of the grip. Out of the two standard versions provided, the narrower version provides greater aiming precision. Its regulation must be performed making sure that the last phalanges of the index finger rest on the trigger. If it has a regulation with less washers, due to the sensitivity of the trigger, the aim will definitely be less accurate.

It is possible to correct setting of the aim if it is too high/low, by acting on the number of washers of thickness of the grip. For example, if the aim is too high, add one or two washers to the upper screw, vice versa if the aim is low. Here is a link illustrating the regulation possibilities:


impugnatura_anim.gif


Remember that one washer should be removed, passing from summer gloves to winter ones and vice versa. As a general indication, normally a hand that wears L size gloves (span opening of approximately 20-21cm) has an excellent level of regulation with 6 washers with 3mm gloves and 7 washers for light summer gloves.

Obviously, the shaft should be substantially straight. To check this, once it has been detached from the heaving line or nylon and after having blocked the barb with a piece of adhesive tape, it should be rotated vertically on the tip. Any possible pleats or imperfections to the shaft will be clearly visible.
I’d suggest contacting Adreno first... that’s probably what C4 will tell
Did you ever try shooting with two hands on the grip?

I don't usually use 2 hands on the grip, this is not my natural way to aim, and it has never been a problem.
 
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Good to see that they are offering decent customer service. That is the only way to have customers coming back for more.
 
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I spoke to the owner of C4 this morning. C4 is going to replace your gun for you with a brand new gun. They'll be in touch with you Hugo, good on you for contacting them.
They have contacted me and will replace grr gun by a Gladius 115
Can’t be more happy
Thank you for your help
 
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Yes, well done Mark as well for putting in a word as that would certainly have helped. Mass producing carbon fiber guns, albeit in limited quantities compared with say alloy tube guns, is not a problem-free proposition and despite best endeavours things do not always work out on some individual guns. The C4 guns are made to a high standard, but you cannot absolutely control every aspect every time. In the tyre/tire industry we often chopped up sample product chosen at random to make sure everything was in the right places after molding, especially when running changes were required if a raw material supply change required new compounding, or a change to cord type in the body plies. Unknown to customers the product was often tweaked to make use of material changes. With spearguns you can chop a few up for examination, but with the economics of producing guns once the “recipe” is right then you keep on making them, with a gun sampled every now and then for actual testing.
 
Yes, well done Mark as well for putting in a word as that would certainly have helped. Mass producing carbon fiber guns, albeit in limited quantities compared with say alloy tube guns, is not a problem-free proposition and despite best endeavours things do not always work out on some individual guns. The C4 guns are made to a high standard, but you cannot absolutely control every aspect every time. In the tyre/tire industry we often chopped up sample product chosen at random to make sure everything was in the right places after molding, especially when running changes were required if a raw material supply change required new compounding, or a change to cord type in the body plies. Unknown to customers the product was often tweaked to make use of material changes. With spearguns you can chop a few up for examination, but with the economics of producing guns once the “recipe” is right then you keep on making them, with a gun sampled every now and then for actual testing.

That's right Pete, that's right.
Through my career in this industry I've been fortunate to have the ear and speak to some of the most successful guys in this industry fairly regularly. Today I spoke to Masahiro Mori (Mori shafts, slip tips, guns) and Marco Ciceri, a name familiar to many as an industry mogul, new owner of C4. As you probably have seen Mori's shafts you know how he is, fanatical more so than most. They're obsessiveness with improvement and perfection drives their need to keep improving and gives them relentless energy. Terry Maas is the same with his contributions and his Freedive Recovery Vest. Marco Bonfanti, founder of C4 is also similar character but was limited by his production capability working in house with more traditional compression tooling and a tighter budget. I can say that after speaking to Marco Ciceri today (lot's of Marcos here) and for the last several weeks about the new gun he's making this much is clear to me: From a production stand point they offer a vast improvement over the Graphite/Urukay/and Mr Dark model predecessors. The consistency in precision in the production quality has drastically changed because they can control the production process much better and consistently. As described above, this wasn't an easy proposition with the prior models. the new guns are a lot lighter, stiffer, and more agile. Furthermore from what I understand each gun has to conform to a set of variables and standards and is therefore slave to that tight standard to ensure what happened with Hugo's gun cannot repeat itself. And that is important in an $800 speargun. In the meantime I am looking forward to playing with one of the new Gladius's underwater and sharing my videos on this Forum first as I enjoy the dialogue again. Clear waters.
 
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Its great that you could straighten this out Mark. But at the risk of being repetitive, why bother if it’s so hard to get carbon fiber right when wood is so much easier? Is pretty and sexy really worth the trouble? What does carbon fiber do better?
 
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