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Japanese Rollerguns owned by Don Paul, his photos

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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popgun pete

Well-Known Member
Jul 30, 2008
Some years back on the Indie speargun thread the topic turned to the Japanese rollerguns. I had spotted two for sale on EBay and informed Don Paul as I knew that he would be interested. Initially only one gun was on offer, the seller then said that there were two. Don Paul asked me if I wanted one, but I replied being wood Customs here might get all excited about them and want to slap a ban on them (wood insects, borers etc.) so I said thanks, but you can have both of them. Long story short, Don Paul sold them not being impressed with their performance and all his photos disappeared in a computer crash. Don Paul had also sent them to me, but my computer, a tower, crashed taking everything with it. But about a year ago I had someone check out the hard drive, the tower was no more, and to my surprise there were Don Paul’s photos. Plus all my other stuff which I was eager to recover.

Now in honour of Don Paul I am putting them up here. The rollerguns were the "King" brand, a slightly later edition compared to the one owned by Jack Prodanovich which was given to him as a curiosity.
Roller Japanese small 045B.jpg

Roller Japanese small 042B.jpg
Roller Japanese small 041B.jpg

Shooting line is crammed under the front clip in bunched loops, there being no line wrap system on these "King" spearguns.
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Here are more of Don Paul’s excellent photos where he is documenting every feature.
Roller Japanese small 039B.jpg

Roller Japanese small 036B.jpg

Note that the shock absorbing sleeves are not present on the left hand gun, they being necessary to avoid a mighty “clack” when the sliding carriage hit the end of travel.
Roller Japanese small 032B.jpg

Roller Japanese small 031B.jpg

Note the brass spears and their brass folded sheet metal sliders.
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The brass spears, unknown to us at the time, had steel slip tips, but these have always been missing until one showed up many years later. All we saw was the brass tips that mounted the missing push on sharp tips.
Roller Japanese small 028B.jpg

Roller Japanese small 022B.jpg

Roller Japanese small 017B.jpg

Roller Japanese small 014B.jpg

Roller Japanese small 007B.jpg

With such great photos gun scholars could finally deduce the operation and purpose of the Japanese rollerguns.
Now you can see a slightly different version in this sketch, this was before they had the brass plate safety that revolved to block the trigger.
Japanese rollergun detail R.jpg
These rollerguns were not originally designed as underwater weapons as I see it, I think they were raft guns initially for the surface interface, such guns being not uncommon in Japan. However with diving as a recreational hunting activity rather than a food gathering chore the rollergun looks like it evolved to take on that task. The proof is the hydrodynamic porpoise back shapes on the sliding carriage, they would not need that refinement for a surface interface shooter. The better safety “switch” is a means to stop jerking firing the gun when you dropped the stretched band rings onto the sliding carriage hooks as the single-piece trigger is not the most reliable when its pivot pin is below the axis of the shaft as it is on these spearguns. Possibly they were used for shooting squid which could be lured in with lights to the surface. The guns came in different lengths and shaft diameters, any given gun was dedicated to that shaft size due to the keyhole shaped muzzle outlet restriction. The anodized alloy nameplates on the guns specify the shaft size to be used.

As the shooting line is now held forward of the roller axle the previous fender straps are no longer needed to keep the line out of the roller band drive system.
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This spear photo showing the tail and tip of the brass spear indicates the cord whipping which is used to secure the tip retention brass ring on some versions. The steel slip tip and its short tether are missing.
Rollergun spear.jpg

This cord whipping would be an impediment to shaft impaling, hence the shaft is intended to deliver the slip tip, not necessarily skewer the victim. Then this photo appeared of another gun offered on EBay somewhat later and we finally saw the missing tip. The presence of corrosion on the brass showed that this gun had seen marine use. Many Japanese rollerguns show no sign of brass corrosion which would indicate that they never have been used, but may have been purchased as a collectable even when brand new.
the slip tip of the Japanese rollergun.jpg

The above gun had a steel shaft, a later replacement by its owner.

More examples of cord whipping on the brass shafts.
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Don Paul decided to put the Japanese rollergun to the test, selecting the less pristine rollergun he fitted it out with flat strap bands made from tyre inner tube rubber. The Japanese rollerguns originally used flat rubber bands that were red, this is the colour given to rubber using clay fillers and contains no carbon black. This type of rubber is often seen on early Japanese dive masks. Note that these are not Don Paul's photos, but another rollergun being similar equipped to explore the band powering system.


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Here we can see the biasing “spring” that adds an opposing torque to counter the gun firing itself, yet another rubber band! Red gummy rubber residues on the brass ring that connects the brass rod link to the trigger indicated that this is how the guns were equipped when new.
Now let us hear from Don Paul himself, this conversation taking place on the aforementioned “Indie Speargun” thread.
Don Paul on the Japanese rollerguns.jpg
One example showed up on EBay being touted as a WWII paratrooper survival tool, but this could just be imaginative spin. To add to “authenticity” the seller showed the gun displayed with a Japanese flag!
jap roller 10.jpg

jap roller 8.jpg

jap roller 7.jpg

jap roller 6.jpg
The elusive slip tip dart of the Japanese rollergun. Another name that they were often sold under was “Tairyo”, all the very early guns bear that name, often in Japanese language labels. English labels appear not long after, perhaps giving a clue to the guns’ actual vintage.
I know that Ron Mullins has a “Tairyo” gun that looks totally unused, but intriguingly it is based on a top slotted grey plastic tube rather than twin brass rails. Now a pusher element sliding down a tube underwater will be functioning as a water pump, so this makes underwater use unlikely for this version which make me think that the gun is now returning to its supposed surface interface shooter roots.

Ron took the above photo, he has a whole bunch of them, but I will leave it to him to describe it. Save to say that the same principles are at work here. This is a much more modern gun, but no indication yet of its age. Questions directed to Japan just receive “sorry, cannot help you” answers, so even there the guns are little remembered.
An example of a complicated surface interface shooter is the Scope Arrow gun, also made in Japan.
Scope-Arrow gun patent.jpg

Scope-Arrow surface interface speargun.jpg

The barrel tube on this speargun is actually an underwater telescope, you sight the gun from a boat or raft with the tip of the muzzle submerged. A good grip on both gun handles is required to not give yourself a black eye, the butt's rubber pad being the telescope’s eyepiece! All you need then is a barrel to put the fish in.
Scope Arrow gun from boat.jpg
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It's interesting that you mention people I've known but never knew these things about their interests. Many years ago Ron Mullins went diving on my boat several times and I went on his boat one time on an overnight trip to Cortes Bank, 100 miles off the SOCal coast. I was aware of his interest in old equipment and recall that he started a spearfishing museum in Huntington Beach, but I didn't know about these Japanese guns. I guess he realized that I wasn't all that interested. I never dove with Don Paul Gaboury but I met him at a couple of gatherings that were tribute to the pioneer of spearfishing and used to exchange emails with him now and then. When I decided to get rid of most of my shell collection from all over the Pacific because most of it was just sitting in boxes in the garage, he was the first to say he wanted it. We had a lot of fun going through the shells when he came to pick them up. I hope they are being displayed somewhere now that he is gone.

I should hasten to say that while I knew these guys, I was never in the same league with them as a diver. I recall that on one trip Ron wanted to take video of me shooting fish. He found a halibut and called me over, and it still took a couple of minutes of him pointing at it before I spotted it. Then he went and sat on the bottom and waited for me to dive and shoot. I knew that there was no rush. He could want a very long time. On another trip he got video of my shooting some yellowtail. This was probably over 20 years ago and before every beginner had a GoPro with his first speargun, so it was relatively unusual to have video of myself diving.
Yes, well I can remember as no doubt you do the use of film in recording underwater action, where any shot was limited by the camera’s film spool capacity and then the wait after processing to see what you ended up with. Often crud in the film gate could spoil a nice sequence, a hair dropping in unnoticed perhaps. Then you have your light meters, your focus distance setting and the concern of too much light and backscatter ruining your shots, like filming in a snow storm underwater with all that suspended reflective grit. Speaking of filming I believe Don Paul had planned to video the Japanese rollergun shooting to see how the shaft flew from the gun. I think that this speargun design was created by the Japanese as it utilised their existing skills in woodwork and bronze metal casting. As for the initial inspiration I believe it was these French side slotted barrel guns, the twin rails pinch hitting for the barrel tubing and running slots. Yves Le Prieur had visited Japan in the thirties, as had Alexandre Kramarenko, the designer of the spring gun. Note that Le Prieur's gun uses flat rubber bands, as does the Japanese rollergun.
Le Prieur's gun without float R.jpg
Then when you add this to the mix you can see where the Japanese rollerguns come from.
Enclosed track band gun.jpg

Here the sliding carriage rides inside a barrel tube, on the Japanese rollergun it rides on twin parallel rails, although one variant of the Japanese rollergun uses a monorail. The juxtaposition of ideas is now obvious. The holes in the carriage "wings" are there to lighten the sliding carriage and to afford a grip to pull the carriage back against the band pull.
cross pollination.jpg
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The angled rear grip on the Japanese rollergun is a sort of truncated shoulder stock which has descended from metal strap or tubular frame stocks, you can see the same configuration on the early Hurricane band gun.
Hurricane Rafael.jpg

Which had originally been designed to look like this when it was named the “Corsair”. The two holes in the rear end of the angled grip are for mounting the shoulder stock frame.
s-l1600 (25).jpg

Hurricane Corsair.jpg

The rear shoulder stock on the “Corsair” was a hollow tubular frame that was claimed to add floatation to the gun after it was cast side to grab the victim. Of even more interest is the gun is also promoted as a weapon to shoot fish from the riverbank or from a moored boat! That means this gun also serves as bridge to water interface shooters, an important tie-in to the supposed use of Japanese rollerguns in the early period.
Hurricane Corsair Rifle.jpg
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The riverbank shooter even continued for a time in the modern era. The Barnett Fish Bazooka is a form of elastic powered crossbow firing a steel shaft.
Barnett Fish Bazooka R.jpg

Riverbank shooting was a big deal in France and may have paved the way for shooting fish with guns underwater, just check out this advert! Note the use of shoulder stocks, a spear is way heavier than a bullet and with no water to slow it down or stop the gun from pushing you backwards.
Arbalete A Poissons advert (800x529).jpg

The crossbow shown above is elastic powered, the bow limbs are simply a solid frame with all the stretchiness in the bowstring, basically an elaborate slingshot. The spear pusher is decelerated by the elastic bowstring slamming into the mid-body vertical posts which then decelerate the slider by stretching the band in the reverse direction. Pretty cool idea I would think.
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