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What we know about barrels


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#1 UV Halo

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Posted 07 August 2009 - 03:18 PM

...can produce porting where the total surface area of the ports is Greater than the surface area of the bore of the barrel.


I'm confused by this description as I can interpret it in two ways:
1. The sum of the interior surface area removed during the porting process > than the remaining interior surface area? (a barrel where you have more material removed, than remaining, like that old rail-based barrel).
2. The sum of the Ported Surface area > the area of the non-ported surface area (i.e. 8" of porting on a 12" barrel).

The stock Phantom barrel for example - it's minimally ported but quite quiet. I think the key might be the channels - they act as a significant step up for the last 1.5" or so.


I don't own a phantom and I've not seen a phantom barrel up close, can you point me to a description or diagram showing this? What I'm picturing is interior grooves (fluting) inline with the length of the bore, for the ported section of the barrel.

#2 brycelarson

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Posted 07 August 2009 - 05:07 PM

...can produce porting where the total surface area of the ports is Greater than the surface area of the bore of the barrel.


I'm confused by this description as I can interpret it in two ways:
1. The sum of the interior surface area removed during the porting process > than the remaining interior surface area? (a barrel where you have more material removed, than remaining, like that old rail-based barrel).
2. The sum of the Ported Surface area > the area of the non-ported surface area (i.e. 8" of porting on a 12" barrel).

The stock Phantom barrel for example - it's minimally ported but quite quiet. I think the key might be the channels - they act as a significant step up for the last 1.5" or so.


I don't own a phantom and I've not seen a phantom barrel up close, can you point me to a description or diagram showing this? What I'm picturing is interior grooves (fluting) inline with the length of the bore, for the ported section of the barrel.



to the first part - the sum area of all of the ports cannot exceed the area of the barrel - ie the bore of the muzzle of the barrel. so, if the barrel is a .690 - then there cannot be more than .37 square inches.

the phantom barrel has only a modest amount of ports - http://www.phantomon...uns/barrels.htm

only 4 holes per row with 8 rows of porting. inside the barrel there are flutes cut into the barrel - about the same length as the porting from the end of the barrel. those flutes line up with the porting. they're about 1/16" deep and a little less than 1/8" wide. so, looking at the front of a phantom barrel - it looks a bit like an 8 pointed star - with each point lining up with a row of porting.

#3 UV Halo

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Posted 07 August 2009 - 05:57 PM

That explains it perfectly! I now see that this is the same patent that described the helical porting.

I would be surprised to hear that a Phantom sounds quieter than an equally ported barrel without the grooves.

#4 Dragon1291

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Posted 07 August 2009 - 10:45 PM

Bryce... You lied.... You said a minute.... :P

I guess the only way to test the porting issue is with a freak kit... I mean, don't they have a rain tip and crap?

#5 Jack Wood

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Posted 08 August 2009 - 02:37 PM

I can give you another bit of information (if you can call it that):

When we were very very friendly with WDP we were shooting Jacko barrels (1-piece stepped bore, very very clever) and we wanted rain barrels (we live in England!) so they made us 1-piece stepped-bore barrels with zero porting.

They were terrible. I don't just mean an anicdotal "not as accurate". I mean shoot-round-corners absolutely un-shootable. I mean un-shootable. More inaccurate then having a break and rain in a barrel.

Bryce, I would be interested to see a test with the Freak Rain tip. Does it have zero porting?
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#6 thumper

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Posted 09 August 2009 - 06:21 AM

great video.. good summary..

Ive have had a long standing opinion that the (acceleration + recovery) time needed is a function of operating pressure.

the higher the initial pressure, the more rapid the acceleration, the shorter the barrel needed to fully the accelerate the ball efficiently (e.g., automags)
the lower the initial pressure, the slower the acceleration, the longer the barrel needed to fully accelerate the ball efficiently

#7 Blue mInI

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Posted 09 August 2009 - 07:33 AM

Hopefully I just educated some people in the chat with this thread.

Thanks Bryce!



Is a .684 a good underbore, because i already have a Dye UL kit going and dont want to spend too much to figure out if underbore will work for me, and Dye only makes up to a .684, unless someone knows where i can get a .682 from DYE????

#8 Troy

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Posted 09 August 2009 - 08:39 AM

I can give you another bit of information (if you can call it that):

When we were very very friendly with WDP we were shooting Jacko barrels (1-piece stepped bore, very very clever) and we wanted rain barrels (we live in England!) so they made us 1-piece stepped-bore barrels with zero porting.

They were terrible. I don't just mean an anicdotal "not as accurate". I mean shoot-round-corners absolutely un-shootable. I mean un-shootable. More inaccurate then having a break and rain in a barrel.

Bryce, I would be interested to see a test with the Freak Rain tip. Does it have zero porting?


I don't know what to think about this, it's hard for me to imagine how porting would effect shots THAT much... not that I'm doubting you, I'm just at a loss.
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#9 Troy

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Posted 09 August 2009 - 08:46 AM

great video.. good summary..

Ive have had a long standing opinion that the (acceleration + recovery) time needed is a function of operating pressure.

the higher the initial pressure, the more rapid the acceleration, the shorter the barrel needed to fully the accelerate the ball efficiently (e.g., automags)
the lower the initial pressure, the slower the acceleration, the longer the barrel needed to fully accelerate the ball efficiently


I think this is something that should be looked into, I'd like to see a test with barrels with different control bore lengths between markers with different operating pressures. A mag may be a confusing example, because of it's lower breech pressure, but a test between a Tippmann and a Droid/Geo/Quest/(name your lp spoolie) would be interesting.
\m/

#10 brycelarson

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Posted 09 August 2009 - 08:59 AM

I think this is something that should be looked into, I'd like to see a test with barrels with different control bore lengths between markers with different operating pressures. A mag may be a confusing example, because of it's lower breech pressure, but a test between a Tippmann and a Droid/Geo/Quest/(name your lp spoolie) would be interesting.


I don't know that we actually have breech pressures for too many modern guns. Tom Kaye did a bunch - but that was back a while ago. The problem with the test is that it involves cutting into guns - so it would be really, really expensive. And operating pressure doesn't necessarily have much to do with breech pressure. In the old test (this is off the top of my head - so I might be a bit off) - the angel was the highest breech pressure at 110 psi or so. the Mag was at the lower end at about 60 psi - with a much more gradual power curve - while the cocker was in the middle at 80-ish.

It's been a while so I may be off on those - but I'm pretty certain about the mag and angel - they were sorta the point of the test - TK was showing that operating pressure isn't the same as breech pressure.

but yes, threre should be some relationship between optimal control bore length and breech pressure - the higher the shorter.

The other possibility is that there is something else at work here. Paintballs accelerate really rapidly - a matter of just a hand-full of milliseconds. It's possible that the optimal lengths aren't different enough to matter. I'm totally making these numbers up - so don't take them as some sort of endorsement - but it's possible that the lowest breech pressure of, say 50 psi and the highest at 110 - a ratio of more than 2:1 - might only have a .5" difference in optimal length. say a 10" control bore and a 9.5" control bore.

Since the pressure drops so quickly behind the ball as it moves - the starting pressure will start to even out. so, let's take that same example, 50 and 110 psi.

after the volume behind the ball has doubled now we're looking at 25 and 55 psi, double that again and we're at 12.5 and 22.5. double it again and we're at 6.25 and 11.25. so now we're still at a ratio of 2:1 - but the psi differences are tiny - only 5 psi at this point - so it's possible that the only significant difference goes away so quickly that the optimal acceleration length just isn't that different.

#11 MNpaintball

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Posted 09 August 2009 - 09:26 AM

so based off of what you now know (or what you have known,) what would you think right now for the money is the best barrel out there that does it's job, and does it well?


oh, and a great vid overall i must add. there are going to be people that are going to call "BS" because they will find out their SLY kit or UL barrel isn't worth the money (statistically)

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#12 brycelarson

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Posted 09 August 2009 - 01:48 PM

so based off of what you now know (or what you have known,) what would you think right now for the money is the best barrel out there that does it's job, and does it well?


well, let's see. either a 1 piece or a kit with a long back - overall length 12-14".

CP .685 12" or 14"
CP two piece kit - .682
Freak Jr. in .679+.682

I have a 14" stiffi in .681 here - have not shot it yet - but should be good stuff. 5.5" of .681, then steps up to .700

by my theories the deadly wind CF barrel should be good - along with any kit with long backs (evil pipe kit etc.)

technically the one piece barrels win on efficiency - but since virtually none are what I would consider small enough - I can't just say 1-piece. they tend to be much better price/performance wise. Any small bore one piece you can get our hands on is a good move.

#13 FireFrenzy

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Posted 09 August 2009 - 02:54 PM

I felt like i was back in all sorts of review papers or abstracts from the reading i have to do for my internship... and here I was thinking i had a vacation:P Very well done vid with a good review portion of the availible data...

#14 Troy

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Posted 10 August 2009 - 07:35 AM

after the volume behind the ball has doubled now we're looking at 25 and 55 psi, double that again and we're at 12.5 and 22.5. double it again and we're at 6.25 and 11.25. so now we're still at a ratio of 2:1 - but the psi differences are tiny - only 5 psi at this point - so it's possible that the only significant difference goes away so quickly that the optimal acceleration length just isn't that different.


This is exactly why I would like to see it tested. I would really like to see how breach pressure relates to bore length... but like you said, operating pressure and breach pressure don't necessarily correlate so breach pressure would have to be tested first.

I would love to see the breach pressures for a bunch of markers posted up... figuring out if that effects control bore length would be gravy.

Is there any reason why you couldn't drill into a barrel and put a sensor there as close to the breach as possible instead of drilling into the marker? Yes, you'll prolly get slightly lower pressures than TK did, but you wouldn't have to scrap an otherwise perfectly good marker. As long as the distance of the placement of the sensor, the bore size of the barrel, and the diameter of the paint were consistent, than I would consider this an acceptable measure.

Furthermore, I think this would be a cool way to test the different breach pressures that result from different paint/bore combinations... which would be cool to know as well.
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#15 maddog3904

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Posted 10 August 2009 - 09:11 AM

I can give you another bit of information (if you can call it that):

When we were very very friendly with WDP we were shooting Jacko barrels (1-piece stepped bore, very very clever) and we wanted rain barrels (we live in England!) so they made us 1-piece stepped-bore barrels with zero porting.

They were terrible. I don't just mean an anicdotal "not as accurate". I mean shoot-round-corners absolutely un-shootable. I mean un-shootable. More inaccurate then having a break and rain in a barrel.

Bryce, I would be interested to see a test with the Freak Rain tip. Does it have zero porting?


I own both the rain front and the AA front, so I can give some information on this. The rain front does have zero porting (hence rain front), however I have found that this has made no impact on accuracy. The major difference between the rain front and the AA front is the direction of sound. Without porting, all the noise is directed forward out the barrel, toward the target. It sounds about the same as the AA front to the shooter, but if you stand down range you can tell the difference. My personal choice between the two is the rain front. The reason? Its extremely easy to clean barrel brakes....Of which I've never had while playing.

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#16 brycelarson

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Posted 10 August 2009 - 09:21 AM

I own both the rain front and the AA front, so I can give some information on this. The rain front does have zero porting (hence rain front), however I have found that this has made no impact on accuracy. The major difference between the rain front and the AA front is the direction of sound. Without porting, all the noise is directed forward out the barrel, toward the target. It sounds about the same as the AA front to the shooter, but if you stand down range you can tell the difference. My personal choice between the two is the rain front. The reason? Its extremely easy to clean barrel brakes....Of which I've never had while playing.


do you have a backyard to shoot in? Can you do a 50' test - just grid up some plywood, lock the gun down and shoot 20 shots with each front?

#17 NovaPB

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Posted 10 August 2009 - 09:30 AM

The only problem with under boring is it is not trivial to do. The ability to under bore is dependant on the paint available (i.e. field paint) to you and the limited selection of barrels on the market. If you can't get a real under bore, you may be inadvertently matching. Since barrel/paint matching results in worst consistency, this needs to be avoided. Thus, under boring needs to be avoided unless you can be sure you are truly under boring. If you cannot reliably under bore, your next best option is to overbore.

Basically, you cannot just say buy barrel X and you will be under boring. The wise player will still have an under and over bore barrel and check the paint when they play.

Point in case, the paint we had to use at the BT Big Game on Saturday either rolled out of my 0.682 CP 2 piece or wedged in tight (needed a squeegee to push out). Paint was rolling out of 0.679 freaks as well. Performance from my 0.682 was terrible. The chrono was all over the place as well.

While I agree with under boring in theory, until barrels become available to get a true under bore, IMO you are better off taking the efficiency hit and over boring than risk the poor consistency of a paint/barrel match. Ironically, you should do exactly what the manufactures recommend via their stock barrels and over bore.

Edited by NovaPB, 10 August 2009 - 09:32 AM.


#18 Special Ed

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Posted 10 August 2009 - 09:36 AM

...can produce porting where the total surface area of the ports is Greater than the surface area of the bore of the barrel.


I'm confused by this description as I can interpret it in two ways:
1. The sum of the interior surface area removed during the porting process > than the remaining interior surface area? (a barrel where you have more material removed, than remaining, like that old rail-based barrel).
2. The sum of the Ported Surface area > the area of the non-ported surface area (i.e. 8" of porting on a 12" barrel).

The stock Phantom barrel for example - it's minimally ported but quite quiet. I think the key might be the channels - they act as a significant step up for the last 1.5" or so.


I don't own a phantom and I've not seen a phantom barrel up close, can you point me to a description or diagram showing this? What I'm picturing is interior grooves (fluting) inline with the length of the bore, for the ported section of the barrel.



Here's some pics showing the inside of the Phantom barrel. There are channels for all the ports as well as a slight step increase of the ID.

Posted Image
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#19 brycelarson

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Posted 10 August 2009 - 09:37 AM

thanks ed.

#20 nickp

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Posted 25 August 2009 - 03:47 PM

Okay i just have a question. When you shoot a paintball out of the barel while under boaring the paintball will squeze into the barrel creating a oblong shape and when it comes out of the end of the barrel its going to try to change shape during in flight which will cause some drag and turbulance. Wont this cause a decrease in acuracy? I know with underboaring this will still happen but not as much so overboaring is more acurate?
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#21 brycelarson

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Posted 25 August 2009 - 04:17 PM

Wont this cause a decrease in acuracy? I know with underboaring this will still happen but not as much so overboaring is more acurate?


the fluctuation in shape is so small that it doesn't cause a measurable change in accuracy. I mean, the largest underbore I've had is something along the lines of .007 or .008. That's a couple of human hair thicknesses.

Again, it's about scale. It's possible that a 690 ball through a 670 back would cause such paint deformation that there would be a negative effect. I don't know.

#22 Leftystrikesback

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Posted 25 August 2009 - 04:27 PM

It actually doesn't change shape much at all. I did a finite element analysis on it in a thread about 6 months ago and it shows changes in roundness of something like 10^-5 inches.

The boundary layer of air (the uniformly flowing region) separates from a sphere and turns into a turbulent wake well before the 90 degree line (80 degrees in laminar flow, I think something like 65 in turbulent), so a small deformation at the 90 degree line would not affect the turbulence or wake much at all. It seems to me that the paintball's seam would do more to affect the turbulence / wake because based on it's orientation, it could affect the point of BL separation.
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#23 MNpaintball

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Posted 25 August 2009 - 04:29 PM

another question for you punkworks guys, but i don't know if it has been answered yet...

Can the length of a barrel effect the FPS consistency while shooting? especially when underboring, does the length of the barrel effect this?
i was wondering if friction was a factor between the paintball and barrel, and if the paintball would ever get "caught up" on the barrel if it was a little longer.

is this a simple NO?

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#24 MNpaintball

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Posted 25 August 2009 - 06:19 PM

anyone?

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#25 brycelarson

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Posted 25 August 2009 - 09:02 PM

Can the length of a barrel effect the FPS consistency while shooting? especially when underboring, does the length of the barrel effect this?
i was wondering if friction was a factor between the paintball and barrel, and if the paintball would ever get "caught up" on the barrel if it was a little longer.


you're actually asking two questions here.

first, there seems to be a slight correlation between barrel length and consistency. It looks like shorter barrels are more consistent. the two piece barrels were a touch more consistent than the one-piece barrels. So, if I had to guess what the most consistent barrel was - it would be a barrel with between 6 and 12" of underbored control bore with between 2 and 4" of overbored, ported end after that. It looks like the shorter the part of the barrel in which the ball is accelerating the more consistent.

to the second part of the question - yes, at some point the barrel will start to slow the paintball. the 16" barrel shot just a bit less efficiently than the 14" barrel - in a one piece constant bore situation. This means that somewhere between 14" and 16" the friction on the ball starts to slow it down before it exits the barrel.

#26 MNpaintball

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Posted 25 August 2009 - 09:45 PM

ok.
so it seems that the optimal set up for a barrel would be a freak kit with a .682 or .679 bored back with a tip that made the total length around 10"? that is, if there ever was an optimal barrel set up.

another question then, could you put into perspective how much or little these air efficiencies really are?
like a 5% gain in efficiency from overboring to underboring? 10%?

i'm just curious in what you guys have found in your very numerous tests with barrels...

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#27 brycelarson

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Posted 25 August 2009 - 10:46 PM

ok.
so it seems that the optimal set up for a barrel would be a freak kit with a .682 or .679 bored back with a tip that made the total length around 10"? that is, if there ever was an optimal barrel set up.

another question then, could you put into perspective how much or little these air efficiencies really are?
like a 5% gain in efficiency from overboring to underboring? 10%?

i'm just curious in what you guys have found in your very numerous tests with barrels...


I'll pass this along to a person better with physics than me. We saw something along a 20-25 fps change from largest bore to smallest bore. That's out of aprox 275 fps - so we're looking at 10% increase in speed - at the highest end of things.

Sorry, I'm not remembering right now - can someone chime in here - that equates to how much energy savings?

oh, and the freak is prob a bit shorter than optimal for control bore length. the one piece barrels were slightly more efficient. I've got a possible test in the future that would give a better answer about what the optimal control bore length would be. I'm going to go out on a limb and say that it's going to be more like 10"

Edited by brycelarson, 25 August 2009 - 10:48 PM.


#28 Leafy

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Posted 25 August 2009 - 11:09 PM

back to the discussion about control length and porting. In the AGD studies I swear TK said something about the ported section of the barrel being practically useless except for reducing sound, I'd like to disagree, ever try shooting just a back? So the ball must still be accelerating even in the ported section of the barrel.

#29 cockerpunk

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Posted 25 August 2009 - 11:13 PM

back to the discussion about control length and porting. In the AGD studies I swear TK said something about the ported section of the barrel being practically useless except for reducing sound, I'd like to disagree, ever try shooting just a back? So the ball must still be accelerating even in the ported section of the barrel.


it is. in out testing the CP backs showed significantly less FPS then the back plus a 2 inch front which was ported.
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#30 Leafy

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Posted 25 August 2009 - 11:16 PM

back to the discussion about control length and porting. In the AGD studies I swear TK said something about the ported section of the barrel being practically useless except for reducing sound, I'd like to disagree, ever try shooting just a back? So the ball must still be accelerating even in the ported section of the barrel.


it is. in out testing the CP backs showed significantly less FPS then the back plus a 2 inch front which was ported.


and I experienced this on a gun that most of us assume to have a high breach pressure, 98c. It was impossible to get the velocity over 220 fps but it seemed to be very consistent at that.

#31 Leftystrikesback

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Posted 25 August 2009 - 11:18 PM

I'll pass this along to a person better with physics than me. We saw something along a 20-25 fps change from largest bore to smallest bore. That's out of aprox 275 fps - so we're looking at 10% increase in speed - at the highest end of things.


From this test data the largest bore (.696) shot 9 fps slower than the smallest bore (.682). 9 / 286 = 3.1% slower. But the biggest difference in efficiency was actually between the smallest bore and the bore that matched the paint (.686) with a difference of 11 fps. 11 / 286 = 3.8% slower.

That's just velocity change, the change in efficiency is calculated from the energy used like bryce said. Energy is proportional to velocity squared so the biggest difference in efficiency is between the paint-bore match and the underbore at ((286^2) - (275^2)) / (286^2) = 0.075 So paint to bore match is 7.5% less efficient than underboring.

Between Overbore and underbore, the overbore is 6.2% less efficient.
((286^2) - (277^2)) / (286^2) = 0.062

Obviously all those values are from limited test data with some error. I used the data from barrels of the same length so that the only differences being compared are bore size. There are larger drops in efficiency when you combine overboring with say a really short barrel.


Edit: Haha wow there were 3 posts durring the time it took me to do that. sad for me.

in out testing the CP backs showed significantly less FPS then the back plus a 2 inch front which was ported.


This is interesting. Just goes to show that as long as there is some pressure difference in the barrel the ball will keep accelerating.

Edited by Leftystrikesback, 25 August 2009 - 11:23 PM.

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#32 Leafy

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Posted 25 August 2009 - 11:21 PM

I'll pass this along to a person better with physics than me. We saw something along a 20-25 fps change from largest bore to smallest bore. That's out of aprox 275 fps - so we're looking at 10% increase in speed - at the highest end of things.


From this test data the largest bore (.696) shot 9 fps slower than the smallest bore (.682). 9 / 286 = 3.1% slower. But the biggest difference in efficiency was actually between the smallest bore and the bore that matched the paint (.686) with a difference of 11 fps. 11 / 286 = 3.8% slower.

That's just velocity change, the change in efficiency is calculated from the energy used like bryce said. Energy is proportional to velocity squared so the biggest difference in efficiency is between the paint-bore match and the underbore at ((286^2) - (275^2)) / (286^2) = 0.075 So paint to bore match is 7.5% less efficient than underboring.

Between Overbore and underbore, the overbore is 6.2% less efficient.
((286^2) - (277^2)) / (286^2) = 0.062

Obviously all those values are from limited test data with some error. I used the data from barrels of the same length so that the only differences being compared are bore size. There are larger drops in efficiency when you combine overboring with say a really short barrel.


so does that 6% go directly to shot count, like if I get 1900 shots off my protege with a wicked over bored barrel that I'd get 2014 shots a 114 shot increase? Or am I not understanding?

#33 brycelarson

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Posted 25 August 2009 - 11:43 PM

so does that 6% go directly to shot count, like if I get 1900 shots off my protege with a wicked over bored barrel that I'd get 2014 shots a 114 shot increase? Or am I not understanding?


yup that should be right.

#34 Leafy

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Posted 25 August 2009 - 11:45 PM

holy crap.

#35 MNpaintball

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Posted 25 August 2009 - 11:45 PM

From this test data the largest bore (.696) shot 9 fps slower than the smallest bore (.682). 9 / 286 = 3.1% slower. But the biggest difference in efficiency was actually between the smallest bore and the bore that matched the paint (.686) with a difference of 11 fps. 11 / 286 = 3.8% slower.

That's just velocity change, the change in efficiency is calculated from the energy used like bryce said. Energy is proportional to velocity squared so the biggest difference in efficiency is between the paint-bore match and the underbore at ((286^2) - (275^2)) / (286^2) = 0.075 So paint to bore match is 7.5% less efficient than underboring.

Between Overbore and underbore, the overbore is 6.2% less efficient.
((286^2) - (277^2)) / (286^2) = 0.062

damn you're smart.

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#36 Pearlsea

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Posted 25 August 2009 - 11:50 PM

This should be stickied :|
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#37 Leftystrikesback

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Posted 26 August 2009 - 12:10 AM

so does that 6% go directly to shot count, like if I get 1900 shots off my protege with a wicked over bored barrel that I'd get 2014 shots a 114 shot increase? Or am I not understanding?


Good question... the simple answer is yes.
If you want to get more complicated it's less than that because you can't use all the energy stored in your tank (ya know, you can't shoot below a certain pressure and all that), but still a close approximation.

holy crap.


Yeah it doesn't seem so trivial when you put numbers to it huh? I didn't really realize how significant it was either until I did the math just now. That $30 .682 CP back practically pays for itself.
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#38 kenzie

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Posted 26 August 2009 - 05:51 AM

great video helps alot
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#39 Troy

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Posted 26 August 2009 - 06:55 AM

I'm wondering when we will see a Punkworks edition Stiffi or CP built to Bryce's specs...
\m/

#40 brycelarson

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Posted 26 August 2009 - 08:20 AM

I'm wondering when we will see a Punkworks edition Stiffi or CP built to Bryce's specs...


never a PunkWorks edition. We want to maintain our independence. If we work with a company and put our name on a barrel - then we certainly have removed all barrel testing from what we can do w/o bias.

As to someone building a barrel to what I think are the optimal specifications - sure. This information is all public. If a barrel manufacturer happens to find what we do interesting enough to spend half an hour on the phone - then they're going to get some ideas from me. If they choose to implement those ideas - then I'll test the barrel and see if it really is better. If it is - I'll say so, if it's not - then I will tell them that - but if PunkWorks name is on it - then we're stuck.

We are working on a program to verify manufacturer claims. We won't be endorsing the product - but we are talking about allowing companies to use our name. This would only be if we can replicate the results they want to claim. There would be no exchange of goods or money - simply our agreement that what they're claiming is a real, repeatable result.

#41 Coconut

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Posted 26 August 2009 - 07:58 PM

NVM. Shoulda read just one post earlier.

Edited by Coconut, 26 August 2009 - 07:59 PM.

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#42 thumper

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Posted 30 August 2009 - 03:33 PM

I ran a small test today..

marker : 98 Evolution Sniper, PPS stab @ 350psi, Belsales valve, Belsales ventuti bolt, co2, temp : 87 degrees, big red chrony

paint: Procaps Visible Impact - solid orange shell, pink fill - small (75% roll outs on .679)

maybe 6 balls w/ each barrel, swapping barrels back and forth twice.
firing slightly uphill to ensure no roll out effect on velocity.
------------------------------------------------------------

12" new style kaner .682 w/ nail polish wedgits : velocity 270-272

10" freak w/ AA tip and .679 aluminum insert : velocity 260-264

From what I gather here is the longer kaners (7" I think) backs seem to improve efficiency relative to
a smaller bore barrel.

#43 BEASTY

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Posted 30 August 2009 - 04:10 PM

Maybe this will eliminate all "what berral should i buy" threads.

Thanks bryce!

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#44 staypuft

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Posted 10 September 2009 - 12:43 AM

this goes out to bryce or cockerpunk, have you ever shot a sanchez machines sm1 orbium 2 barrel? the back is almost 6" they do have weird bore sizes, they have .680, .683 and .686. would this make some kind of difference since they are not the normal size bores?

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#45 brycelarson

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Posted 10 September 2009 - 08:00 AM

this goes out to bryce or cockerpunk, have you ever shot a sanchez machines sm1 orbium 2 barrel? the back is almost 6" they do have weird bore sizes, they have .680, .683 and .686. would this make some kind of difference since they are not the normal size bores?


I would assume performance like the CP two piece kit. those has a 5.5" back.

as to the sizes - no, they should land right in line with every other kit. basically, if the control bore is the same length and porting is similar - then they should fall right into line - the smaller the bore the more efficient.

#46 staypuft

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Posted 10 September 2009 - 08:16 PM

So underboring would still be good when using apex tips? Would it affect the back spin since it is being squeezed out of the barrel and not so much as to being pushed out

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#47 TROPICALPUMKIN

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Posted 28 September 2009 - 11:22 PM

do scratches on the inside of barrel front effect accuracy
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#48 D.K.

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Posted 29 September 2009 - 07:53 AM

do scratches on the inside of barrel front effect accuracy

nope (i've read your thread)

#49 brycelarson

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Posted 29 September 2009 - 08:10 AM

do scratches on the inside of barrel front effect accuracy


at some point - yes, it looks like they might. the one barrel that we had shoot poorly had a very poorly honed interior. you could see variations on the inside finish of the barrel. it wasn't smooth and shiny. so, from that I would assume that scratches, at some point, would effect how the ball leaves the barrel. the direction and location on the interior might change how many and how deep those scratches need to be to have an impact.

now, normal wear and tear on barrels haven't shown any changes. We've shot barrels that were brand new and barrels that were heavily used. the normal surface blemishes that you see inside a barrel don't seem to have any effects.

what kind of scratches are you talking about?

Edited by brycelarson, 29 September 2009 - 08:11 AM.


#50 TROPICALPUMKIN

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Posted 29 September 2009 - 09:47 PM

They were caused my a squeegee and it is one that is the most noticable in the barrel front(luxe) there are none in the insert the scratch is in the shape of a circle
it was caused by one of these squeegees the rings on it are plastic http://paintballgate...rayacaputh.html

also would polishing the inside of the barrel get rid of these and if so what king of polish and will if affect the barrel at all
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