Torch mount for 40mm pneumatic barrels?

[Fibonacci]

I've been searching high and low for a suitable mounting system that will allow a LED torch to be mounted securely onto a 40mm pneumatic barrel.
While there are plenty of torch mounts to suit firearm Pictatinny rail systems I haven't found one that fits pneumatic spearguns!

The closest I've come across is the Beuchat 40mm reel adaptor, which could be modified to attach a torch:
https://spearfishing.com.au/collections/reels/products/beuchat-reel-adaptor-for-tubular-barrels

Any other tips gratefully received...!

 

[Diving Gecko]

Yeah, I would have recommended something like that, too.
Omer makes one as well: https://www.diveshop.gr/index.php/c...ategory/91/?___store=en&___from_store=default

Personally, I'd probably 3D print one and I wouldn't mind the challenge nor would I mind sending you one - but this is my busy season with work and I have some other projects already on the back burner. I don't think I could get around to this one before March or so.
Perhaps ask around back home to see if you know anyone with a printer? Materials could be as simple as the cheap and easy to print PLA. Only tricky part would be to draw it up in CAD. Not to difficult if you have a bit of experience with it, but not easy if you don't.

 

[Fibonacci]

Thanks Gecko... my day job involves a lot of 3D CAD so will have a play and see what I can come up with... I've got a few SCUBA parts queued in front of this project.
CNC machining from Delrin could also be an option for a small run... if there is enough interest?!

 

[popgun pete]

Maybe something like this laser attachment.

or this from Pelengas https://www.ebay.ie/itm/151720672583

in stock here http://barrakuda.eu/lv/?route=product/product&product_id=1090&currency=EUR

 

[Fibonacci]

Hmm... some interesting takes on this, thanks Pete!
I was heading along a Picatinny rail solution, mainly because of the myriad of cheap accessories available online... literally hundreds of different torch mounts!
Something like this 30mm scope mount scaled up to 40mm ID could work, easily angled to the RHS to clear the line spooling out on the LHS.
Swap out the alloy socket screws with 316 stainless... and the torch mount is QD via the button.

 

[popgun pete]

The Pelengas mount is a Styrofoam molding to provide buoyancy to offset the weight of the torch, otherwise the gun would be nose-heavy. The torch looks like a waterproof Skyray Dive Torch as I have one of those, but not for spearfishing.

 

[popgun pete]

With the power of small LEDs it should be possible to make a ring of lights on the muzzle in a housing like a doughnut or a beam from either side. Button cells could power it and a rotating switch be built into the mount on the gun nose cone with outrigger line wrap hooks.

 

[Zahar]

My design of the location of the laser designator!

 

[popgun pete]

I brightened the image so that we can see it better.

 

[popgun pete]

The Beuchat reel mount would hold a pretty large torch with modifications, but the real issue is to set the parameters of what the torch will be used for. In night hunting, which is illegal here, the speargun mounted light provides a flood field to pick up fish in the darkness at the edge of the pool of light. Then you swing the beam and the gun on target, so you need a big head torch like the one shown in the Pelengas advert. If you want a narrow beam of light for under a ledge then the torch can be a bit more compact and then the weight/buoyancy issue will not be such a problem. Ideally the torch and mount should have a neutral effect on gun buoyancy. Some years ago I proposed a light for the Sporasub “One Air” built as a pair of LEDs in that gun’s wide nose cone shroud. The "One Air" Nightfighter model looked rather like a Cobra snake, image is attached.

 

[popgun pete]

There are some very compact and bright LED torches available these days https://www.newfrog.com/es/product/...2-3IDuiR1IhAMOWES7xUIDH9VVTBF_3MaAstZEALw_wcB USB recharging, these compact LED torches use 18650 lithium ion rechargeable batteries.

 

[Fibonacci]

Thanks Pete, the underside of that Beuchat mount looks like it would take a flat Picatinny rail, depending on the length and hole spacings.
Either that or a torch mount may actually be able to clamp around the two existing flange recesses... which would act as recoil buffers too!

 

[popgun pete]

Thanks Pete, the underside of that Beuchat mount looks like it would take a flat Picatinny rail, depending on the length and hole spacings.
Either that or a torch mount may actually be able to clamp around the two existing flange recesses... which would act as recoil buffers too!
View attachment 52987

Weight is still going to be a problem, so you need to provide extra buoyancy somewhere. When a couple of years ago I first saw the Pelengas torch holders I thought why make them out of Styrofoam as that seemed not such a good idea durability-wise, then I realized that it was all about the buoyancy offset for the added mass of the torch.

 

[Fibonacci]

Agree the Pelegas sized torch would need quite a bit of additional flotation, but I just need a small compact LED torch to illuminate under ledges and big boulders... by the time my eyes have got used to the gloom the fish have usually bolted!

 

[popgun pete]

Check out this small torch used on the Ocean Rhino band gun. The mount could be adapted to strap under a pneumatic speargun muzzle.

 

[Fibonacci]

How about a laser sight/torch combo on a Picatinny mount

https://www.ebay.com/itm/Tactical-R...2HYjBN2uFOhPanMyuO_g:rk:7:pf:1&frcectupt=true

 

[popgun pete]

Interesting that you should show that as I am awaiting a delivery of this unit.
https://www.newfrog.com/es/product/...mm-11mm-mount-size-hunting-laser-sight-215216

 

[Fibonacci]

Aha... I assume it is X-Y adjustable for zero?
I wish speargun manufacturers would include integral Picatinny rail mount points in their muzzle underside and handle upper designs...
Looking forward to your review in due course...

 

[popgun pete]

When mainstream speargun manufacturers are looking for the next “big thing” it may happen, but I expect that small scale producers may make it happen earlier by 3D printing conversion rail mounts for spearguns. Then when any bugs are sorted out permanent moldings dies may be created to pump them out in volume and at very low cost. Given that China has produced these current mounts for firearms at such low prices it only needs someone to sense a market opportunity in underwater weapons and then it will happen.