C4 Graphite shooting line not sitting tight around the line release? Help?

[marco15499]

Yeah, and some websites state that their guns have an effective reach of 25'...

I would stay on the "light side". I don't like to use both hands to shoot a speargun.

 

[popgun pete]

Well being more used to these guns I will not be having any trouble. They shoot 3/8 shafts with 3/4 bands.

 

[Savagedragon]

Here it is straight out of the shipping box and cut free of meters of bubble wrap and an outer protective clear bag which was inside the box. Took about half an hour to free it which was good as another gun I purchased a month ago arrived snapped clean in two (fortunately not one of these) as it was in a package that served only as outer cladding and the gun stock bore all of the shipping weight (effectively doubling the weight of the gun) when it was dropped or something was dumped on top of it during shipping.
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Your Urukay basically has the same line release arm design as my graphite,
Could you please put a shaft on it and run a shooting line through the line release arm and let's see if it has the same problem as I do or not?

 

[popgun pete]

I sourced the 7 mm shaft out of my Nemrod “Hellfire Elliptic” and loaded it into the new “Urukay” and took the following photos. The line release lever presses against the tail end of the spear with the trigger mechanism locked up and that is as far forward as it swings.

 

[popgun pete]

It would appear that you have either a short spear tail, which is unlikely, or the shaft is not fully latched in your gun. You can use the annotated close-up photo as a check and compare it with your gun as C4 guns have near identical rear ends. Incidentally the trigger mechanism appears to be stainless steel rather than titanium and the trigger has "C4" engraved or moulded in it as you can see in the photos. If the latter then the actual trigger piece may be titanium. Titanium usually has a silvery grey look compared to stainless steel, but it depends on the treatment applied to it and the actual titanium alloy used.

 

[Savagedragon]

I tried with a different shaft. The original shaft in my C4 was a Pathos 7mm. Since I just bought a Salvimar Hero which comes with a salvimar 7.5mm shaft, I used it for my Graphite. The difference is there. The Salvimar shaft pushes more against the line release arm, therefore with this salvimar shaft the line release arm doesn't do as far forward as it does with the Pathos shaft. So the problem is with the Pathos shaft, I think.

 

[popgun pete]

The important dimension is the length of the tail past the spear retention notch which is the curved notch under the shaft. In the shaft I used there is a transverse hole in the extreme rear of the shaft for attaching the shooting line through there, but I never use it. However it is the standard tail for most euroguns as running a cord loop into the sear box is usually an option. Tabbed or finned shafts have a line attachment hole through one of the shaft tabs, so they don’t have the rear transverse hole and that means the shaft tail end will be that much shorter, however some may be longer and not have the hole.

Sear levers that have a backing projection need a certain spacing so that when the spear tail rolls the sear lever on spear insertion the sear tooth lines up on the spear tail retention notch. However in the C4 trigger mechanism there is no backing projection as the sear lever assembly is sprung upwards and shafts are released by being pulled out by the band tension and overwhelming the biasing springs. In this latest mechanism the line release arm acts as a spear tail stop so that the round sear tooth lines up on the spear tail retention notch.

If you check the C4 website they actually tell you this in a rather round about way, but it only makes sense once you realise what they are talking about.
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).

Just a clarification, I think "nose cone" in the second mention in the above sentence refers to a line slide as metal line slides used to have trailing legs to affix the line to, or had a metal clip with a line loop hole drilled in it. C4 guns don''t use line slides as they use loop attached spears either through a transverse hole in the shaft or a shaft tab.

 

[Savagedragon]

The important dimension is the length of the tail past the spear retention notch which is the curved notch under the shaft. In the shaft I used there is a transverse hole in the extreme rear of the shaft for attaching the shooting line through there, but I never use it. However it is the standard tail for most euroguns as running a cord loop into the sear box is usually an option. Tabbed or finned shafts have a line attachment hole through one of the shaft tabs, so they don’t have the rear transverse hole and that means the shaft tail end will be that much shorter, however some may be longer and not have the hole.

Sear levers that have a backing projection need a certain spacing so that when the spear tail rolls the sear lever on spear insertion the sear tooth lines up on the spear tail retention notch. However in the C4 trigger mechanism there is no backing projection as the sear lever assembly is sprung upwards and shafts are released by being pulled out by the band tension and overwhelming the biasing springs. In this latest mechanism the line release arm acts as a spear tail stop so that the round sear tooth lines up on the spear tail retention notch.

So the Salvimar shaft is the brown one and the Pathos is the white metallic one.
I don't see much difference regarding the spear tail, see the pics.
When I insert the spears into the mechanism and push the line release arm all the way forward, you can see the difference. The pathos shaft just doesn't push against the line release arm the way the salvimar shaft does.
So what do you suggest?

 

[popgun pete]

So the Salvimar shaft is the brown one and the Pathos is the white metallic one.
I don't see much difference regarding the spear tail, see the pics.
When I insert the spears into the mechanism and push the line release arm all the way forward, you can see the difference. The pathos shaft just doesn't push against the line release arm the way the salvimar shaft does.
So what do you suggest?

Read the third paragraph as you missed it while I was also typing. Basically C4 have not allowed for tabbed shafts because their tails are too short..

 

[Savagedragon]

Read the third paragraph as you missed it while I was also typing. Basically C4 have not allowed for tabbed shafts.

I didn't really get what they mean. In simpler terms, what should I do, practically?

 

[popgun pete]

You need to use a shaft tail that is longer. I see from your photos that those spear tails do have a rear transverse hole, but are very short as they have been cross-drilled right behind the spear tail's shaft retention notch. The shaft I used is the one supplied with the Apnea Amarok guns which is what the Nemrod "Hellfire" actually is, just with new stickers and badges. There will not be much in it, just a few more millimetres in tail length. I only put that shaft in to try things out, but I will be going up to 8 mm for the “Urukay”.

If you want to use the shafts that you already have then you need to add a forward bump on the line release lever to "take up the slack", although it would be easier to take the lever out and make a new one using that existing one as a pattern. If C4 are alert to the changing dimensions then they should make a new line release lever to use with the slighter shorter tail spears.

 

[Savagedragon]

Thanks Pete. Do you have any recommendation of a spearshaft brand that makes longer tail spears? I am in Europe so any European brand would be great!

 

[popgun pete]

Salvimar offer a range of shafts, you might try those. Best to go to a dive shop with a note of the length of your existing shafts and look for some that are longer in the tail, the transverse rear hole will be slightly further back. There are small tabbed shafts that are welded on, they will not pull out like some of the molded in tabs used to do, just make sure the shafts are straight as some are not. I use Riffe shafts in my guns and JBL from their earlier production as the later stuff is said to be not so good, but most of my JBL shafts are rather old as I bought a whole bunch of them years ago. Shafts get used up, they get bent or are lost.

 

[marco15499]

I had a gun with a similar problem and I solved it putting a small "ball" of epoxy at the tip of the line release. You can take it off anytime if you don't like it.

 

[popgun pete]

Don't be afraid to unscrew the socket head screw and remove the line release lever. C4 have provided the second hole in the sear box roof if you want to switch the line release lever over to the right hand side of the gun, so it can be removed without worrying about affecting any adjustments as there are not any. You can do some measurements by temporarily affixing the lever on top of the housing and measuring the distance from the leading edge to the front of the sear box roof. Then measure the spear insertion distance by measuring how much shaft disappears into the sear box from the front edge of the sear box, pull the shaft forwards to take up any slack before measuring. The difference in these two measurements will be how much longer the spear tail needs to be.

The differences in length can easily be seen in a direct comparison. The rear hole is further back on the above tails and intrudes into the spear tail retention notch space on your two shafts. Probably to save money as a tiny bit off say 10 thousand shafts saves a lot of metal as it all adds up.

 

[Savagedragon]

I had a gun with a similar problem and I solved it putting a small "ball" of epoxy at the tip of the line release. You can take it off anytime if you don't like it.

and the epoxy will stick hard to the metal even in sea water?

 

[popgun pete]

Epoxy will stick if the part is clean as a whistle before you apply the epoxy. To clean the lever remove it and drop it in boiling water which will remove anything on it, then tip it out onto a cloth after draining off the water and let it cool off. The epoxy wants to be flat enough so the lever will pass back through the slot when you remount it. Personally I would just change spears, you can always use those spears in other guns, assuming that you have a couple of spare guns.

 

[popgun pete]

So in summary all the conjecture about gun changes and subsequent problems is based on people not looking more closely at their spears. C4 Carbon have been churning out the same guns, all they did was shift the line release from the barrel into the top of the trigger mechanism. In both cases the shaft controlled the line release action, first by blocking its rotation in the lateral direction and then by the extreme tail end blocking it in the fore-aft direction. I don't have many eurogun shafts because I mainly use American and Australian derived band guns, but all my eurogun shafts have long tails and that for many years was the standard.

 

[marco15499]

It will stick. I'm not as perfectionist as Pete is, but cleaning the area with some alcohol and letting it dry is usually enough. I used the two-component thing they sell in the hardware stores. It lasts for months. It's just a little ball in the tip of the line release. Make sure it doesn't interfere with the line release movement.

 

[Savagedragon]

Don't be afraid to unscrew the socket head screw and remove the line release lever. C4 have provided the second hole in the sear box roof if you want to switch the line release lever over to the right hand side of the gun, so it can be removed without worrying about affecting any adjustments as there are not any. You can do some measurements by temporarily affixing the lever on top of the housing and measuring the distance from the leading edge to the front of the sear box roof. Then measure the spear insertion distance by measuring how much shaft disappears into the sear box from the front edge of the sear box, pull the shaft forwards to take up any slack before measuring. The difference in these two measurements will be how much longer the spear tail needs to be.
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The differences in length can easily be seen in a direct comparison. The rear hole is further back on the above tails and intrudes into the spear tail retention notch space on your two shafts. Probably to save money as a tiny bit off say 10 thousand shafts saves a lot of metal as it all adds up.
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Do you think this shaft here:

PLANETMULTISTORE.COM - Omer Shaft Spring Steel Hr 7 Mm | 130 cm | Freediving - Spearguns - Spear Shaft | Planet Multi Store

High resistance harmonic steel rod Large fins and matte finish - Spearshaft Lenght: 130 cm - Freediving - Spearguns - Spear Shaft - SH142115 - 8017736142166 - Planet Multi Store

www.planetdivestore.com

Will work better for my C4? The hole seems to be also further back.