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Tanio Koba rifled inner barrels


Maple-Leaf

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I put one in my G36 DMR set-up recently, and it seemed to make a real difference to the accuracy, range and trajectory of my shots. In other words, the BBs seemed to fly farther, flatter, faster and tighter than before. And I didn't need to use as much hop-up either.

 

Has anyone else had experience with them? And/or done a real side-by-side comparison with standard barrels and smooth tight-bore barrels?

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The air will travel in the rifling, preventing the bb to touch the barrel. It works best with weapons around 1J. And yes, this have been discussed in plenty before ;)

 

Edit: Commando showed his special forces skill; in and out before anyone notices :P

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Correct. Whereas the hop-up rubber actually makes contact with the BB in order to make it spin backwards, the rifling works by creating a swirling vortex around the BB - both causing it to spin and also cushioning it within the barrel (preventing it from bouncing off the insides as it traverses the length - thus ensuring a smoother, flatter, straighter flight path).

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Correct.  Whereas the hop-up rubber actually makes contact with the BB in order to make it spin backwards, the rifling works by creating a swirling vortex around the BB - both causing it to spin and also cushioning it within the barrel (preventing it from bouncing off the insides as it traverses the length - thus ensuring a smoother, flatter, straighter flight path).

 

you are rite in most of this, but i am pretty sure that the bb does not spin.

if the bb did spin, it would cause the hopup to switch directions during the bb's flight causing a screwed up flight pattern.

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how are these in tm hi-capas? i need a tightbore and these seem fairly cheap.

No idea. I was going to get one for my M1911A1 when ever I got around to ordering overseas. I suppose if you used it with .25g BB the range and accuracy should be fairly impressive if the TK-Twist rumors are true.

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I tried one in a completely stock Hi-Capa and fired it off hand from 10 and 20 metres. The groupings did change and I think it was for the better. Instead of having a steady spread, the majority of shots were in a tighter group and there were only a few "fliers", which expanded the max size of the grouping to the same as with a stock barrel. I was using .2g BBs. Maybe I should check it out once more with .25grams.

 

The outer barrel and slide of the Hi-Capa has some noticeable wobble in front, so before you do something about that the accuracy won't improve significantly no matter what inner barrel you use.

 

-Sale

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you are rite in most of this, but i am pretty sure that the bb does not spin.

if the bb did spin, it would cause the hopup to switch directions during the bb's flight causing a screwed up flight pattern.

 

As I understand the principle behind this stuff - it is that the rifling creates a vortex in the barrel, and that it is this swirling air vortex that imparts some lateral spin on the BB.

 

A hop-up unit on the other hand puts back spin on the BB.

 

Theoretically, lateral spin should create a flatter, more accurate flight path than the backward spin does - because its not working against the direction of flight.

 

Has anybody seen a proper scientific description / explanation? I only know about rifling from knowledge of real-steel...

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Ah never mind - trust us Cannucks to sort it out. :P

 

http://www.airsoftcanada.com/showthread.ph...ba+twist+barrel

 

"Tanio Koba TWIST Inner Barrels.

 

--------------------------------------------------------------------------------

 

After years of hearing and reading endless debates about Tanio Koba Twist inner barrels, and after years of hunting for them, I've finally acquired a couple of them in various lengths for various guns from AEGs to GBBs.

 

Here are my initial findings:

 

These inner barrels shoot STRAIGHT. They have an extremely predictable, flat and straight flight trajectory. Where standard hop up will cause the BB to gently curve up before dropping, TWIST (or cyclone) inner barrels will cause the BB to go extremely straight for an even further effective range before dropping.

 

To set a clear and definitive answer for all the debates that have floated on the internet for years:

 

Q1. "How is it physically possible to have a rifled barrel impart a spin on the BB and combine it with the Magnus effect of the hop-up? It is two totally different axes of rotation!"

A1. Actually, the barrel ISN'T "rifled" in the standard sense of a real gun. Yes, the inner barrel has spiral rifling grooves in it, but the BB does NOT touch the groove. The purpose of the TWIST inner barrel is not to put a rifling spin on the BB. It is to put a "cyclone" of air around the BB, to help float it through the inner barrel and PREVENT the BB from touching the side walls of the inner barrel at all. The result of this is higher accuracy, more predictable trajectory and greater effective range.

 

Q2. "I've heard about power requirements for these inner barrels. Details?"

A2. What you've heard is true. The twist inside these inner barrels are optimized for guns that shoot NO MORE than 1 Joule or 330fps with 0.20g BBs. Some internet debates claim that if you have a higher powered gun, all you need to do is use heavier BBs to slow down the velocity of the shot. NOT TRUE. The air moving around the BB will still be beyond 1 Joule and it will affect the shot trajectory.

 

Q3. "What happens beyond 1 Joule or 330fps with 0.20g BBs?"

A3. Up to 330fps, the results of the shot and even the shots dropoff are very predictable, accurate and flat. Groupings remain tight with very little spread. However, once the velocity of the shot begins to exceed that limit, the shot starts to become unpredictable with increased spread. The higher the velocity, the greater the perceived spread.

 

Q4. "So how accurate are these inner barrels compared to other brands such as Prometheus, KM TN or Systema?"

A4. At this time, I have not done any quantitative comparitive range testing to get accuracy results. When used within its optimized power range, I can outright say that these inner barrels have a MUCH straighter trajectory, greater effective range and a generally much more predictive flight path than any other barrel I've used before.

 

There is a project underway for an indoor range test to compare various lengths of these barrels against other barrels at different power ratings (stock, 1Joule and 400+fps).

 

How do I like these inner barrels? I love them. I wish they worked well at 400fps. At 360fps, they are still very acceptable and I will take that in to consideration when using them in some of my guns.

But for now, I am FOR SURE putting these inner barrels into all my pistols and low powered AEGs."

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Maple-Leaf: The Twist barrels certainly don't impart any lateral spin on the BB. The Hop Up in fact prevents the BB from spinning laterally, because it has a gyroscopic effect in addition to creating a lift.

 

If there was any lateral spin, the flight path would indeed be very funky. Ever tried tilting an airsoft gun a little bit sideways when shooting?

 

-Sale

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ever fired an old "gunze sanyo" spring pistol with LRB system ?

 

they had rifled barrels which imparted a spin on the shot as this was before Hop-up was invented.

the range was outstanding (compared to everything else at the time) but the path the shot took was "interesting" to say the least !

it made a big loop from leaving the barrel to finally coming back to the point of aim towards the end of the range.

this meant you could literally shoot around the person you were aiming at if they were between the gun and its extreme ranges.

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