[cockerpunk]

ktap, on Jan 4 2009, 11:22 PM, said:

for sake of argument and clarity, lets say there is a constant and even pressure down by the clock spring of the loader when inactive, and a higher but still constant pressure when feeding.

this is my logic, the loader puts out a certain amount of force, and each ball has 3 tangent points of contact, ball underneath or bolt, side of feedneck, and ball above. since each additional ball only adds a very small surface area, the net force of the loader is not significantly diminished. less time spent under this pressure the smaller the chance of a loading fracture, so a shorter stack seems to, in theory, reduce the amount of loading fracture. However i do agree with Troy that there may be an optimal stack length, but overall i think it would be relatively short.

i think the ideal stack length would be zero ...

[Jack Wood]

In our experience of several different "loading systems" a shorter stack will lead to more fractures.

Paintballs do have a certain amount of elasticity in them (we know this, as you would never get a bouncer if they didn't) and certainly the more there are in the stack, the more the force of the loader mechanism is distributed through the paintballs between breech and loader.

But that is only really true if we are talking about High Force loaders trying to achieve High ROFs. It should make no difference at all how long the stack is, as long as the loader is "tuned" to the stack lenght, ROF requirement, and Paintball fragility of the complete system.

Jack

[Jack Wood]

New Video:

http://www.youtube.com/watch?v=j9WJoWtjAeA...feature=channel

Any comments?

It's uploading to Google vids now so you can download it and play it in Quicktime and frame advance it.

This post has been edited by Jack Wood: 09 January 2009 - 03:28 AM

[Poe]

Jack Wood, on Jan 8 2009, 06:56 AM, said:

New Video:

http://www.youtube.com/watch?v=j9WJoWtjAeA...feature=channel

Any comments?

It's uploading to Google vids now so you can download it and play it in Quicktime and frame advance it.

Looks great. Thank you.

[Jack Wood]

Google Vids

http://video.google.com/videoplay?docid=-1...93843&hl=en

In the "Details" tan in the top right, scroll to "Download Video - iPod/PSP" and then play the vid in Quicktime. You can then frame advance the video.

Jack

[Lord Odin]

Really cool video, Jack! Thanks for sharing it.

It looks like the the ball, despite having split in half, travels forward a little bit before the gas found a weak spot on the bottom side. There, it was able to slip past and blow out, further ripping the ball by grabbing that end of the shell. You can see the paint and even the gas push from the bottom up towards the top of the barrel after it passes the ball. It almost looks like all of the gases want to go around the mass in the middle (broken shell and paint) rather then blow through it. If you look near the bolt, it seems to me that the majority of the paint is remaining stationary and the gas blowing around it is slowly stripping the paint away rather than just blowing the blob into smithereens. Perhaps the high gas flow would explain why the first few inches of breaks are clean on the barrel. The gas is moving so fast that it doesn't give the paint and shell a chance to hit the walls.

Jack, do you know how far back in the action that ball was broken? Did it happen in the loader, feedneck, breech, etc?

[Jack Wood]

Lord Odin, on Jan 8 2009, 12:51 PM, said:

Really cool video, Jack! Thanks for sharing it.

It looks like the the ball, despite having split in half, travels forward a little bit before the gas found a weak spot on the bottom side. There, it was able to slip past and blow out, further ripping the ball by grabbing that end of the shell. You can see the paint and even the gas push from the bottom up towards the top of the barrel after it passes the ball. It almost looks like all of the gases want to go around the mass in the middle (broken shell and paint) rather then blow through it. If you look near the bolt, it seems to me that the majority of the paint is remaining stationary and the gas blowing around it is slowly stripping the paint away rather than just blowing the blob into smithereens. Perhaps the high gas flow would explain why the first few inches of breaks are clean on the barrel. The gas is moving so fast that it doesn't give the paint and shell a chance to hit the walls.

Jack, do you know how far back in the action that ball was broken? Did it happen in the loader, feedneck, breech, etc?

It fell down from P3 with a crack in it. The crack grew as it hit the breech and more again when another ball plumped on top of it.

Yes, the speed of gas seems to keep the paint off the sidewalls for a little while.

[Jack Wood]

Willie, and TechPB have been very very kind in offerening to host higher resolution files of our videos.

This is a trial, so here is the first one.

If you all like this format, we will go ahead and make all the videos available like this so that you get to see everything in much better detail.

http://www.techpb.com/videos/PE%20Videos/B...ak_complete.mov

Please let us know what you think.

Cheers, and thanks Willie!!

Jack

This post has been edited by Jack Wood: 08 January 2009 - 11:47 AM

[moyster14]

Jack Wood, on Jan 8 2009, 10:25 AM, said:

Willie, and TechPB have been very very kind in offerening to host higher resolution files of our videos.

This is a trial, so here is the first one.

If you all like this format, we will go ahead and make all the videos available like this so that you get to see everything in much better detail.

http://www.techpb.co...ak_complete.mov

Please let us know what you think.

Cheers, and thanks Willie!!

Jack

Pretty cool vid Jack.

I couldn't get the new download to work. It says something about not being able to read the source file.

[Jack Wood]

moyster14, on Jan 8 2009, 03:32 PM, said:

Jack Wood, on Jan 8 2009, 10:25 AM, said:

Willie, and TechPB have been very very kind in offerening to host higher resolution files of our videos.

This is a trial, so here is the first one.

If you all like this format, we will go ahead and make all the videos available like this so that you get to see everything in much better detail.

http://www.techpb.com/videos/PE Videos/Barrel_break_complete.mov

Please let us know what you think.

Cheers, and thanks Willie!!

Jack

Pretty cool vid Jack.

I couldn't get the new download to work. It says something about not being able to read the source file.

Please try it again. There was a problem with the way I copied the link, sorry.

Barrel Break Download

Jack

This post has been edited by Jack Wood: 08 January 2009 - 11:50 AM

[moyster14]

I like it. It looks a lot better.

[cockerpunk]

amazing jack. thats exactly the way i imagined the failure during the barrel break test, but not knowing what caused the failure of the ball itself. thats the exact type of pattern we saw in the barrel for every barrel break during out test.

very good evidence that the loader and loading cycle seems to be much more of an issue in terms of breaking paintballs then the barrel and power pulse.

great work. thanks for all you have done.

i am very interested to see your videos in the bouncing balls and the possible mid barrel break.

This post has been edited by cockerpunk: 09 January 2009 - 04:31 AM

[Jack Wood]

cockerpunk, on Jan 9 2009, 09:15 AM, said:

amazing jack. thats exactly the way i imagined the failure during the barrel break test, but not knowing what caused the failure of the ball itself. thats the exact type of pattern we saw in the barrel for every barrel break during out test.

very good evidence that the loader and loading cycle seems to be much more of an issue in terms of breaking paintballs then the barrel and power pulse.

great work. thanks for all you have done.

But wait until you see the videos that I CANT show you just yet!! You may have to re-calibrate your thinking again.

[lovebunny]

nice vids. realy intressing to watch whats going on

[Poe]

Jack Wood, on Jan 9 2009, 04:31 AM, said:

cockerpunk, on Jan 9 2009, 09:15 AM, said:

amazing jack. thats exactly the way i imagined the failure during the barrel break test, but not knowing what caused the failure of the ball itself. thats the exact type of pattern we saw in the barrel for every barrel break during out test.

very good evidence that the loader and loading cycle seems to be much more of an issue in terms of breaking paintballs then the barrel and power pulse.

great work. thanks for all you have done.

But wait until you see the videos that I CANT show you just yet!! You may have to re-calibrate your thinking again.

Awww. Come on.
You can show us.
We won't tell.

[Jack Wood]

Some more HSV footage of something diiscussed here previously. 2 quite clear ways that the leading edge of the bolt can cause damage and failure to the second paintball in the stack.

This post has been edited by Jack Wood: 11 May 2009 - 06:25 AM

[Frozenmedic]

oerllikon, on Nov 9 2008, 10:37 PM, said:

Is there a such thing as an "Air Hammer" (Like a water hammer) could it be the air hitting the ball suddenly?
Or is it a weak wall on paint?

That is a close guess to what I think may be happening. Weak paint is the overall problem, but a solution I'd try is this: Turn down the input pressure and increase the velocity knob. This is like increasing the dwell, so the valve is open longer but delivering less pressure over more time. With high pressure input you have the valve open for a brief time (turning down the velocity screw) ((Assuming you have a cocker style system for a pump) This will put less stress on the weaker paintballs as they are propelled down the barrel. If the valve is open too long (velocity screw up to high) you may get blowback with a semi auto, but this situation is a pump, so you probably won't open the breach before the valve closes again.

Also the bolt slaming into the ball could start the process of structural failure on the paintball when it comes forward to load, again more for a cocker, where you would want the LPR turned down as much as possible to just cycle the bolt and cock the hammer, but with a pump if you got a little carried away slaming it forward, you may apply to much force to the ball all at once.

[woodsballer414]

May i suggest you dumb stuff down more often? As techno-savvy as I am I'm having a hard time understanding some of this. Makes me wanna go back to my real guns.

[tyronejk]

Sorry for the necro, but has anyone reached any definite conclusions about this? From the video with the glass barrel, it looks like it's just friction against the barrel that breaks the ball, possibly air pushing the ball against a side as it moves forward.

[Master_Chief]

the sudden increase of air pressure on the ball forces the contents of the ball to a lower pressure but is countered by the solid barrel which puts increased stress on the weakest point of the ball plus the friction of the ball traveling down the barrel resulting in a fracture of the shell which causes a break. This is my best hypothesis