TK hop twist barrels, are they worth it?

[deepsix]

hehe... I love these discussions!

 

Just to add my own two-cents to this mess;

 

My thought on the TK was always that the "rifling" was to stabilize the air behind the BB, and float it, allowing the air to "stack-up" behind the BB and provide a uniform non-turbulent cushion. The pitch of the rifling is tuned to below 1j. At above 1j of power, my thought is that the air is now PASSING the BB (blow-by, via the rifling channels), and screwing up the intended effect by creating turbulence in front of the BB... which would cause all-sorts of accuracy problems and bounce. I believe a higher pressure/velocity version could be made by increasing the pitch of the grooves... matching the forward momentum of the "swirling air pocket" to the velocity of the the BB. But with Japanese imposed power limits... no need for him to invest in that.

 

Of course I could be wrong... but it never really seemed like such a big mystery to me. I do believe any increases in range (without going into LRB's, since I have no first-hand knowledge) is just perception due to increase in accuracy. An inaccurate barrel can swerve a BB not just left or right... but down and up as well... which would decrease the linear range. Time in the air (with-out hop effects) is entirely dictated by simple physics (gravity).

 

Put it this way, if you drive a car at X speed for Y time... a car traveling in a straight line will go farther (linearly) than one that did the same speed and time but was swerving all over the place.

 

eh, feel free to rip it apart...

[Stealthbomber]

P.S. Stealthbomber, the KSC Glock series have a very finicky hop-up system, so it could very well explain why one pistol outranged the other. In your latest post you said that the one with a Hop-Twist barrel was able to hit targets at a greater range. But did you compare the trajectory, ignoring groupings?

I think I said before but, in more detail, I happened to discover that a guy at my site had an almost identical pistol to me except for the TK barrel. I'm not a great believer in tightbore barrels for pistols. I just don't think that, in a skirmish, there's sufficient need for tack-driving accuracy.

 

Anyway, after a game, as we were walking back to the safezone, we started taking shots at each other at ever increasing range.

I didn't pay a great deal of attention to stuff like the wind direction or the light. It was in a wooded area though and there's rarely any strong wind. It seemed that, once we were more than about 20m apart, I could no longer take casual shots and hit him whereas he didn't seem to be struggling at all. Eventually (at about 30m), I was taking properly-aimed, 2-handed shots and my BBs were just wandering off-course whereas his shots were still traveling perfectly straight.

When we got back to the SZ I complimented him on his shooting and I got quick go of the gun and (in my usual casual test) I simply tried hitting trees roughly 25m away and managed it with no trouble. I tried the same thing with my own gun and hit maybe 3 out of 5 times.

 

My gun isn't over-hopped. The BBs travel horizontally but it just seemed that the TK barrel allowed more accuracy.

Course, again, we're talking about a TK vs a standard KSC barrel. I have no idea if a different tightbore would have yielded similar or better results.

[Delfi]

Course, again, we're talking about a TK vs a standard KSC barrel. I have no idea if a different tightbore would have yielded similar or better results.

 

That's a good call.

 

I wonder whether it isn't just a better tightbore and the 'fliers' that are reported aren't just due to a BB hitting the wrong ('rifled') spot on the upper inner barrel.

 

That would explain why a shorter barrel is more accurate.

 

D

[PlasticMag]

Having used a TK barrel in an AEG, I'll also say that I got more range than I should have. It's all anecdotal, and I haven't used a TK barrel in years (the cheating kiddies here necessitate a bit more... 'oomph'), but I was definitely getting more range out of the gun. Several players at the game remember it, though I doubt they're registered here.

 

That said - any claim of insane AEG range increase should be discounted immediately. I simply got maybe 50 feet more than I should have with the velocity I was using, and at the end of the path there was certainly a much less tight grouping. I know Zero-Ops in Japan swears by the TK barrel + Firefly hopup combo, and I've seen their amazing long range builds for myself (and worked on the externals of one of their builds), but I haven't had a chance to empirically test them in a game environment.

[evo12]

That said - any claim of insane AEG range increase should be discounted immediately. I simply got maybe 50 feet more than I should have with the velocity I was using, and at the end of the path there was certainly a much less tight grouping. I know Zero-Ops in Japan swears by the TK barrel + Firefly hopup combo, and I've seen their amazing long range builds for myself (and worked on the externals of one of their builds), but I haven't had a chance to empirically test them in a game environment.

 

Zero-Ops are my good friends. Which build did you help on or what build are you talking about.

 

edit: Stealthbomber: Prom 03s are garbage. While the fps jump may be there for a +10-15 fps, the added range is terrible. You get better accuracy and range any day with a PDI 05, KM 04, or hop twist. Between a PDW length hop twist and Prom 03 in my mp5k, I got a good 50 ft of range difference (straight trajectory, not lobbing or diving).

 

Sale: Yes, call up any Hawaii retailer and they will tell you that between a Prom 03 and hop twist in the 330 fps and below setup, the TK will float out the longer distance. The only shop that wouldn't use TK barrels would be First Factory for obvious reasons. Plastic mag already cited one shop that uses it over a conventional barrel in certain setups.

 

On another note, you should try to test the barrel in an aeg at distances over 10-20 meters. At 10-20 meters, it's hard to tell true range. The 310 fps AK was hitting past the 200 ft mark (which was measured with a range finder from multiple angles)

[mprojekt]

<returns with a bag of popcorn to share with the rest of the audience>

[Stealthbomber]

<returns with a bag of popcorn to share with the rest of the audience>

<considers suspending mprojekt for trolling and spam>

 

Seriously.

[asinapple8805]

deepsix, i think what you just said was exactly what i said a little earlier.

 

Plastic mag, Zero-Ops (aka Team Killer Studios USA) is a Hawaii based tuning group that tunes according to Japan styles, not a Japanese tuning group (although there are a lot fo Japanese people in it). i know because they are my friends also.

 

Stealthbomber, that's the point that Evo and i have been trying to get across, it works well on shorter barreled guns, but you won't see that much of an improvement on longer barreled guns. Also, the improvement in range and accuracy isn't that much greater if you were to tune both guns very well however it is noticable and it's always nice to have peace of mind.

 

Sale, the only way to really benefit from a twist barrel is during actual skirmish play on a field. sitting on your chair in the comfort of your own home/apartment, and firing at soda cans placed in the room across the way won't show you much.

 

to all you people out there, i think the last time i mic'ed a TK barrel it WASN'T a "tightbore." try it for yourself and you might be surprised that a non tightbore with rifling can outperform a tightbore without.

[mprojekt]

to all you people out there, i think the last time i mic'ed a TK barrel it WASN'T a "tightbore." try it for yourself and you might be surprised that a non tightbore with rifling can outperform a tightbore without.

 

The first thing I noticed while reading up about the TK barrels is that they're are pretty loose.

 

This appeals to me since it would make our group's AEGs a bit more forgiving in the dirty environment that we play in.

[Glenn]

edit: Stealthbomber: Prom 03s are garbage. While the fps jump may be there for a +10-15 fps, the added range is terrible. You get better accuracy and range any day with a PDI 05, KM 04, or hop twist. Between a PDW length hop twist and Prom 03 in my mp5k, I got a good 50 ft of range difference (straight trajectory, not lobbing or diving).

 

 

So you operate under the assumption that BB's have velocity, spin and barrel as quantities describing their kinetics? To the point where twist barrels provide more range, but some non twist barrels actually hinder range without effecting velocity or spin?

 

Are you absolutely serious? We're back to magic bolts.

 

 

If you install a barrel, twist, 6.01, 6.5, whatever, and you procede to gain velocity, while losing[/i] range, turn the hop up. If that doesn't fix it, you did something wrong.

 

How about someone postulates what BB characteristic could possibly keep it in the air longer. Its got spin, its got velocity...I'd love to hear what else there is. Vorticity in the barrel isn't a BB property. Koba Magic dust is a marketing term. The BB doesn't take a spin along the bore axis.

 

 

 

A BB with X Velocity and w rotational velocity behaves Y. It just does. How you get to X and w don't matter, they always make Y. If a TK barrel some how allows a BB to retain its w hop while traveling at X, you'll get Y range. Now a non TK barrel may require a little more hop to get the same final w at the muzzle (having lost a bit more bouncing in the non TK barrel). The consequence is a little less X. So it may not enjoy the same range.

 

BUT if you have two guns, shooting BBs from the same bag, at the same velocity, optimially hopped, the ranges WILL BE THE SAME.

 

 

Edit:

Was anyone here a paintballer around 99-2000? Back then, the magic 'venturi bolt' was all the rage, and if you read the forums, added all sorts of range to your paintball gun. How? The Venturi effect, of course. Now, discounting that they didn't actually use the Venturi effect, at all, and looking at the bolts objecticely, all the did was rob you of some efficiency (star face bolts have a greater K factor than a classic round face), and, some of them did, at least, distribute the propellent blast over more area of the paintball, reducing breakages.

 

Now, lots of guns still use Venturi style bolts, but its such a non issue that it doesn't even get mentioned on the boxes of low end markers.

 

People used to say ported barrels gave them more range.

 

People STILL say they're cool low pressure set ups give them more range.

 

People say their brass barrels give them more range. No, their ceramic barrels. Nope, their TiNi barrels.

 

The moral of the story? People will believe anything if they want to enough.

[PlasticMag]

Evo- they built an AK for someone ages ago that I did some external work on way after the fact. Sorry, don't know more details.

[Stealthbomber]

The moral of the story? People will believe anything if they want to enough.

I was gonna say this before...

 

Once upon a time a mate asked me to fit a Systema barrel in their M4.

For a bit of a laugh I took his stock barrel out, stuck it in a drill and polished the outside of the barrel with wire wool to a mirror finish, just like the Systema barrel I was going to fit.

That weekend he was full of praise for his new barrel. Better groupings. More accuracy and better range.

 

If I wasn't such an honest guy, I would have left it at that.

However, I decided to tell him what I'd done - in front of everybody at the skirmish.

 

I think he's forgiven me by now.

 

Anyway, I think the message there is clear.

 

[PlasticMag]

That's not quite a valid comparison - that's someone with arguably less technical skill or knowhow than necessary to fit a barrel, vice the installer of the barrel who should be able to tune it properly and see what's going on.

[evo12]

So you operate under the assumption that BB's have velocity, spin and barrel as quantities describing their kinetics? To the point where twist barrels provide more range, but some non twist barrels actually hinder range without effecting velocity or spin?

 

Are you absolutely serious? We're back to magic bolts.

 

 

If you install a barrel, twist, 6.01, 6.5, whatever, and you procede to gain velocity, while losing[/i] range, turn the hop up. If that doesn't fix it, you did something wrong.

 

No, i'm saying that PDI .05, KM 04 and twist will give better range and accuracy than a Prom 03 although Prom 03 will give a bigger fps jump than the others. FPS does not necc. mean more range.

[Glenn]

velocity, spin

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The moral of the story? People will believe anything if they want to enough.

 

[evo12]

I came to this conclusion from actual testing, installation of the barrels , and shooting in the field. I trust my findings. I'll leave it at that.

[mprojekt]

No, i'm saying that PDI .05, KM 04 and twist will give better range and accuracy than a Prom 03 although Prom 03 will give a bigger fps jump than the others. FPS does not necc. mean more range.

 

Curious.

 

Is that the Prommies have poor tolerances down the length of the bore?

[asinapple8805]

I'll answer for Evo, Yes.

[Sale]

Stealthbomber, you're mean and cruel to have done that! But it serves to prove the point without a shadow of a doubt: When you believe you have some better parts in your AEG, you could swear that you get a better range and groupings in the field.

 

It would have totally cracked me up if your buddy started arguing back and claimed that your polishing work somehow improved the range, even though the phenomena could not be explained or ever replicated in a proper test.

 

I came to this conclusion from actual testing, installation of the barrels , and shooting in the field. I trust my findings. I'll leave it at that.

What "actual testing"? Did you or did you not fire the AEG at various ranges with different barrels, and what were the results?

 

As we saw from Stealthbomber's example, psychology messes up any test that consists of simply playing with the gun. It's a completely understandable thing to be mistaken like this, as it's human nature. But it takes a fool to trust their subjective observations over the laws of physics.

 

Ever noticed how the sound of F1 cars seems to lower when they drive past you? I have a couple of questions: Do you think the pitch actually lowers, or does it just seem like that to you because of where you're standing? What would you say if someone tried to convince you that the doppler effect is a lie and you should just stand next to the track and trust your ears?

 

-Sale

[PlasticMag]

But psychology doesn't explain the users who, like me, buy the barrels NOT EXPECTING ANYTHING, and then find to their pleasant surprise that good things happened. Psychology also explains why people who have pre-formed negative opinions of them confirm their own hypothesis.

 

Again, these aren't magic, but they DO provide a slightly increased range (from experience), and definitely tighter groupings (as everyone seems to agree).

[Glenn]

So you paid for that barrel, without expecting better performance?

[Stealthbomber]

So you paid for that barrel, without expecting better performance?

That would have been my question too.

[PlasticMag]

So you paid for that barrel, without expecting better performance?

 

Yep. I had a KM 6.04 tightbore in before, and figured 'what the hell, might as well give it a try. Sounds odd but could have potential.'

 

I sold the KM tightbore (wish I had kept it for a later project, but hey).

[Sale]

But psychology doesn't explain the users who, like me, buy the barrels NOT EXPECTING ANYTHING.

Yet later you say: "Sounds odd but could have potential"

 

Placebo can have an effect even on people who try to convince themselves that they aren't expecting anything. A human is the master of self-deception.

 

Psychology also explains why people who have pre-formed negative opinions of them confirm their own hypothesis.

True, but it mostly affects the perception of the performance. A fair test doesn't lie, and I dare call myself professional enough to make an unbiased test. If anything, I'm a Tanio Kobayashi fanboy for everything he's done to Airsoft, especially the GBB pistols which are my favorite airsoft gun type.

 

Again, these aren't magic, but they DO provide a slightly increased range (from experience), and definitely tighter groupings (as everyone seems to agree).

A slight increase in effective range can be achieved simply by better accuracy. The travel distance of the BB isn't changed.

 

I'd just like to end this thread already, so here's the word of God:

 

In this fashion it keeps regular trajectory effect with the balance of hop up rubber. Therefore, it improves grouping quality, but it doesn’t improve the range and the muzzle velocity in comparison with the normal hop up barrel.

 

There you have it. The increased effective range comes from improved groupings, but this goes for any high quality precision barrel, grooves or no grooves. It doesn't make the BBs fly a longer distance.

 

-Sale

[evo12]

So you paid for that barrel, without expecting better performance?

 

Yea, I bought an 05 and a hop twist and borrowed a friends Prom 03 and KM 04. I'm not made of money but if the barrel didn't work out for me, I always could use it for a future project in some other gun. I also bought the barrel when it first came into HI before it hit most of the HK stores and was the "guinea pig" in the group so any preconceived judgments, placebo effect, etc that I had about it was not there.

 

How did I test it? I installed barrel, set hop, fired, measured distance with a rangefinder, switched barrels , repeat process.

 

You guys can go on believing what you want but unless you guys do actual testing firsthand, then you won't see for yourself. Sometimes you gotta try things out instead of doing calculations.

 

I stand by what I said and if you guys ever do play a game with me, you guys are free to see it firsthand. I know otherwise, theres always going to be a reason to doubt me.