roller vs standard speargun, range and penetration

This is a comparison of range and penetration between two 90 cm spearguns.
I tested both spearguns at 5 meters from tip of the shaft to the target.
The results are interesting and completely dispel many wild claims...
I'll add a note because people get confused about pretention. This gun uses multiple tabs and a two step loading procedure. This increases the capacity for pretentioning to the extreme. For instance, the pretention on this gun would make it very difficult to load with a loop. The coeffiscient is 3.7 (not crazy but optimal for this setup).
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[@tomasito292]

FACTS The roller has the same power and accuracy as your 90cm with very little recoil and way less effort in loading. if you made your roller bands just 20% stronger your roller would blow your 90 cm gun out of the water and it will still be easy to load. I made a 110cm roller with 5/8 bands and a 7.5mm 3 sharkfin shaft that has more power and range than my 120cm carbon gun with two tight 5/8 bands and my roller has very little recoil. rollers when properly set up are way superior to two-band pipe guns.

[@potvinr]

I tested a few commercial rollers since this test. I'll revisit the test with new guns... but from what i observe.... overall the rollers dont provide any significant advantage in terms of reach, not anything that would convince me. I still like them though. I'm making three more right now.

[@fishmut]

@@potvinr ... can't wait to see them mate , really enjoying your videos .

[@DeepBlueSpirit2]

This is a very interesting topic. To be able to make a statement is not easy. There are many variables and guns (setup) must be comparable: rubber type, size and age, stretch - type and dimensions of shafts, roller bearing type/size, etc. Roller pros for me are the minimum muzzle recoil and that they are more maneuverable as they are shorter for same shooting range then a standard gun. But also love shooting with a standard double-band 120 gun. At the end probably it is more important to be a good hunter, get closer and land the fish. Thanks for sharing your comparison. All the best! >

[@chrishelmkamp4931]

Does not seem like your bands are =

[@chaochannainoa5178]

I think you should buy a roller gun with the proper setup and you would see that a 90 cm speargun is like a 100 ,to me at least

[@potvinr]

I have tried a dozen rollers at différent time, starting with the old beuchat from 15 years ago. I was never overly impressed and i share the same level of satisfaction with those guns as their owners do (mostly highly experienced competitors).

[@Nickerian91]

@@potvinr Cant really tell i usually make my own "standard guns" and never used a roller but in theory it should be stronger with less recoil and also easier to load. Due to the pulley system - the pull force required to pull the rubber is cut in half (more power and easier to load) - the stretch length is now 100%ish of the gun (no waste of power) while a standard gun stops pulling the spear 1-1.5/3 of the way which is why a longer gun makes a huge difference in traditional guns. - the recoil cancel itself out due to the rubber pushing the gun in both directions at once. based on your results i can imagine you did not make the rollergun rubber short enough

[@benatkin5273]

You have double bands on the regular speargun. Put a single band on it then see which one out performs. A roller with the same band size and number performs like a 30% longer regular spear gun.

[@potvinr]

A roller is a double band gun. The amount of material is very similar.

[@whynottalklikeapirat]

@@potvinr But isn’t the stretch itself different on a longer piece of rubber though?

[@potvinr]

no, it's still stretched 300 to 350%. bands do work the same way on each type of gun.@@whynottalklikeapirat

[@whynottalklikeapirat]

@@potvinr What I am getting at is that there is a relationship between the power of the amount of material and the way it is distributed during accelleration, depending on how that material is shaped and how those factors relate to the weight of the projectile. If you make a sling shot for example and you make a shorter but broader band and a longer, slimmer and slightly tapered one, and the amount of material is the same and you stretch them not to the same lenght but to the same capacity in terms of stored power (so it’s the same), then slightly depending on the weight of the projectile, the long tapered (and consequently further drawn out) band should mostly outperform the short broad one because of the manner in which power is transferred during the acceleration which changes the speed and velocity. I hope I explained that in an understandable way 😂

[@potvinr]

rollers give a less jerky pull on the shaft... that's supposed to make a large difference. it should reduce shaft wip, but it's not always a factor, especially if you use weak bands and stiffer galvanized shafts, on you guns... and inclosed track will do it much better than the roller btw. @@whynottalklikeapirat

[@riclopezvlog2379]

wow amazing speargun.

[@kayb4995]

I think rollers are highly overrated relative to a well set up traditional gun with a reverse mech. Even the results Rob allen got in his shaft velocity tests seem to agree imo. The juice isn’t worth the squeeze unless you really do want or like the no recoil, which is an advantage no doubt

[@tayvin6538]

You need to have pretention on your roller

[@potvinr]

The coefficient is 3.7... Using the two step loading you see here, you could go over 4 and still have some band to grab (but the gun would not shoot well and the elastics would not last long). Basically, if you can load a gun with a loop like you see on normal commercially available rollers, you cannot pretension them very much, at least not like guns with multiple tabs on the bottom.

[@manduz274]

Tks For the Review Broo

[@vovkaswed]

Спасибо!!! Thank you!! My test the same.

[@potvinr]

Awsome, put it online lol..

[@arnelbejo]

What is powerful speargun invert or standard

[@yd8104]

I might be understanding something wrong here but how the comparison can be relevant if you use 1) 2 bands for the traditional one and 2) 18mm bands, while using only one 13 or 14mm band on the roller?

[@potvinr]

It was an example of two common guns that are super similar. I have a video coming were I take a souped up to the max roller, with and without booster band. and it still does nothing special in terms of range or penetration. I like them, but don't expect a miracle. I'd like to see someone do a video showing the exceptional range and penetration of ANY roller side by side with a traditional gun with similarish specs.

[@lukephilpot5660]

@@potvinr The thickness of the band on the Roller is really important. Was it 16mm like the other guns? looks thinner, and hence would perform weaker.

[@potvinr]

@@lukephilpot5660 This was simply a comparison of two family of guns to showcase something I had noticed using a dozen different rollers owned by TOP spearfishermen (and another dozen rollers since then) that rollers are not magical. I'll do another video soon. I have a 130 cm roller well balanced for 16 mm that i will compare to a standard 130 and maybe a Rob Allen roller of the same length. Alas, again they are very close in performance. BTW, the roller in the video works better with 14 mm stretched like crazy than with 16s.

[@SteveBroyles]

interesting analysis. I'd like to see roller vs. traditional w equal coefficient of stretch. 3.7 is really hot. What happens if you make a 3.5 roller and a 3.5 traditional?

[@potvinr]

They would be false equivalences... the roller and the traditionnal are not optimized at the same stretch. I was comparing working setups.

[@Gronky-sv5yp]

Problem with this is that you used a wooden roller. Among makers, Wooden roller are known for the difficultty to find the right configuration. Most of the time it ended up being underpower. One maker told me, that the key here is to find the best stretch and the best diameters for different types of shaft thickness and weight. The best one to start, he said, is 7.5 shft and 16 mm at 350%. Even with those setting, the shots mostly inconsistent. Wooden roller has become some short of litmus test for a speargun maker. Therefore it's very rare you see someone using wooden roller, most used multiple banded convent or a inverted roller. The rollers we see mostly used are barreled, carbon or alumunium. I have a twin banded RA 120 tuna, that i sometimes exchange the muzzle with a roller one, the difference is night and day.

[@notpastranapastrana2403]

@Rene..do you have new vids of a properly powered roller vs trad?

[@potvinr]

I should, but I feel the time of the rollers is pretty much over lol. The good ones will continue to be used, but the almost religious beliefs in attributes that defied physics did not survive the test of actual use by a lot of people. We now know what to expect. BTW, that small gun was overpowered. It had a ratio of 3.7. It works better at 3.4, but no magic.

[@skipperry63]

Thanks! I’m getting ready to buy a roller gun OR an inverted roller gun.

[@potvinr]

I'd go with an inverted. I see more of a difference with them. I only tested small sizes though.

[@skipperry63]

@@potvinr the concept is brilliant and the mechanical advantage would make it easier to load. Thanks!

[@JSJ-mn8wg]

Maybe the pretention on the bands of the roller isn't high enough? What is the shaft diameter and the rubber diameter on the roller?

[@potvinr]

6.5 mm shaft and the pretention is mostly irrelevant (it depends on your initial setup). The band is stretched at 3,7 once loaded. I used quite a few rollers and overstretched bands don't do good anyway.

[@vodice35]

@@potvinr Pretension is everything on roler gun...it must be around 30-35 %...if you dont have pretension on rubbers you dont heve max power. Pretension is basic for roler!

[@mikebooysen3678]

Hey man, from a totally neutral perspective (I was also skeptical about rollers) this video isn't displaying the truth about the roller because your roller isn't set up correctly. Are you using bushes or bearings? The bands look like they have almost zero preload. I would actually say my 90cm roller (Rob Allen) outperforms my 110 and is closer to my 120. I'm meticulous and my guns are all set up correctly. What sucks about rollers is they are hard to set up correctly... Mine frustrated me, and to be honest I don't use it that much because it shoots so differently to a rail gun that I struggle to switch between the two. Appreciate the effort you put in making a video. Perhaps make another one with a different roller? Also, those bands on that 90 look to be a bit overpowered. You will most likely get the shaft going faster with less power applied to it.

[@potvinr]

I need to find five ardent roller guys bring their most souped up rollers and have try to beat normal spearguns. That would probably not help either but it would be entertaining

[@castandspear]

@@potvinr check out the mannysub rollers. My buddies swear by them, but setup is everything

[@potvinr]

@@castandspear I like the mannysub double rollers. We'd have to compare them to four band spearguns. I'm sure I would prefer shooting a double roller over a four band spearguns... the only issue i can see, has to do with the ability to use slip-tips and large shafts on the rollers.

[@fishhunter348]

​@@potvinr double roller is not to be compared to 4 band speargun. The only similarity is the amount of rubber. But on a double roller you load 2 rubbers not 4. Even though you have as much rubber material on double roller as 4 band standard gun, only one end of the rubber is "working" as the other end is anchored. Same thing applies to single roller vs 2 band standard gun.

[@fadizakzouk2084]

Is that a specific type of wood board that it floats like that?? Nice idea for training

[@fishmut]

i think in one of his other videos he said he made it (roller gun) from cedar wood.

[@potvinr]

I normally use iroko, padook or teak, but I make a lot of prototypes in cedar@@fishmut

[@somethingnotmaterial]

What do you think about pneumatics?

[@potvinr]

They work but not a big fan. I hate loading them

[@somethingnotmaterial]

@@potvinr it's just interesting hearing people discussing gains on roller when a pneumatic will blow them all away. I find loading & reloading a pneumatic quicker & easier. I can understand that some people find them difficult. Thing is, even with less pressure loaded they become easier to load & yet still perform better. People talking about adding pressure to pneumatics when they can probably be reduced for most. I'm back on pneumatics now after couple years of band.

[@potvinr]

@@somethingnotmaterial Well, the pneumatics don't do very good in many situations, but they are faster to load than rollers.

[@potvinr]

I think Rob Allen did a pretty good test a few days ago. kzbin.info/www/bejne/fJfRqoR4drKXhLs

[@bluedoggum8373]

Seems to me the roller did outperform, but maybe not by much? And close distances it underperformed. I’d like to see more real world tests like yours. I think the best roller argument is the recoil myself, I’m not sold on the power argument.

[@potvinr]

yeah, no, I now have four rollers. They are fun to shoot but fall short in too many ways to be practical, and even a moderately powerful 3 band gun blows them out of the water. The invert rollers are the way to go if you want something useful, yet non traditional.@@bluedoggum8373

[@stjepkodropulic3915]

Have you tried adding extra parallel bands to your roller gun, attached on the rollers shaft? Something like this kzbin.info/www/bejne/fnKmqaKGrcuBq68 It should give you some extra initial kick.

[@potvinr]

Well i would go for a second roller instead... and it beats the purpose. You might as well get a proper two band gun.

[@islabonita8915]

Ur roller rubber band set up is wrong,..

[@potvinr]

How?

[@aldogjipali2835]

Don't listen to all these guys living in denial about the ability of the roller spearguns because they fell into the marketing hype. Even if your set up can be significantly improved from a physics point of view a classic double banded speargun will always be more powerful than a single roller. The roller might get close if it uses a higher % elongation of bands but it will still be less powerful. The 90 cm roller would be close to a classic 110 gun if it used a single band and that still wouldn't be quite true due to losses. I am a mechanical engineer so I am not talking out of my ass.

[@potvinr]

I do mention ideology muddling opinions. It's crazy how people attach their self worth and pride to opinions about silly things. I'm all for rollers but not for kidding myself.

[@keke_h972]

finally a honest fucking video Subscribing now

[@potvinr]

thanks, I'm still in the process of measuring different roller effectiveness, but yeah, enough with the magic thinking.