[2thdoc]

brycelarson, on 25 September 2012 - 05:42 PM, said:

drg, on 25 September 2012 - 04:20 PM, said:

I know it's another can of worms, and you may have discussed this before, but would reballs be a more consistent projectile for this kind of testing?
How does a reball seam compared to a high end paintball seam?

Reballs are an odd beast. The major problem I have with them is the surface finish. They're not slippery like paint.

Some batches are quite round and have great seams - some don't. Some are consistent in mass, some are all over the place.

We have considered it in the past on numerous occasions but just couldn't find a way to make it relevant to paintball shooting. It's a good thought - and it's possible that with the right product it would be viable, but up to this point we haven't found a way to make it work.

would rifling have any effect on reballs?

[brycelarson]

2thdoc, on 30 September 2012 - 12:09 AM, said:

Bryce, I have read the accuracy data regarding hammerhead (rifled) barrels. It seems that rifling had little effect on accuracy. It seems underboring which you have stated produces spin also reduces accuracy. Would it be a logical consequence to test for consistancy in the x and y axis rather than accuracy in the x and y axis... for all variables...( underboring vs rifling vs overboring) or has this already been done.

I'm not sure I understand the question. The vector calculation is based on the standard deviation for the x and y impact locations. This means that we are somewhat calculating consistency in the vector calculation. A smaller standard deviation would mean a tighter pattern - more consistent flight.

[Troy]

2thdoc, on 30 September 2012 - 12:14 AM, said:

brycelarson, on 25 September 2012 - 05:42 PM, said:

drg, on 25 September 2012 - 04:20 PM, said:

I know it's another can of worms, and you may have discussed this before, but would reballs be a more consistent projectile for this kind of testing?
How does a reball seam compared to a high end paintball seam?

Reballs are an odd beast. The major problem I have with them is the surface finish. They're not slippery like paint.

Some batches are quite round and have great seams - some don't. Some are consistent in mass, some are all over the place.

We have considered it in the past on numerous occasions but just couldn't find a way to make it relevant to paintball shooting. It's a good thought - and it's possible that with the right product it would be viable, but up to this point we haven't found a way to make it work.

would rifling have any effect on reballs?

You're on the right track... I hadn't thought of using rifling on reballs, but the problem is that the rifling on hammer head barrels is on the over bore section of the barrel, so the ball doesn't come into contact with the rifling, so it won't spin it.

[brycelarson]

Troy, on 30 September 2012 - 12:47 PM, said:

You're on the right track... I hadn't thought of using rifling on reballs, but the problem is that the rifling on hammer head barrels is on the over bore section of the barrel, so the ball doesn't come into contact with the rifling, so it won't spin it.

yeah, and reballs are tiny - so they would have even less contact with the rifled portion of the barrel.

[Troy]

brycelarson, on 01 October 2012 - 08:10 AM, said:

Troy, on 30 September 2012 - 12:47 PM, said:

You're on the right track... I hadn't thought of using rifling on reballs, but the problem is that the rifling on hammer head barrels is on the over bore section of the barrel, so the ball doesn't come into contact with the rifling, so it won't spin it.

yeah, and reballs are tiny - so they would have even less contact with the rifled portion of the barrel.

I've seen people make reballs out of modeling clay... I wonder if you made a ball big enough, if you could put spin on it.

[brycelarson]

The problem being with any of these tests is that while it may show what happens when clay or reballs spin - that doesn't necessarily relate to paintballs.

rntlee has shown that surface finish of the ball and seam finish both seem to effect accuracy. I would have to imaging that if gelatin variations matter - then gelatin to clay is going to matter even more.

Unless you're testing on the projectile you intend to use in play tests get WAY more academic and WAS less useful.

[Troy]

brycelarson, on 05 October 2012 - 11:50 AM, said:

The problem being with any of these tests is that while it may show what happens when clay or reballs spin - that doesn't necessarily relate to paintballs.

rntlee has shown that surface finish of the ball and seam finish both seem to effect accuracy. I would have to imaging that if gelatin variations matter - then gelatin to clay is going to matter even more.

Unless you're testing on the projectile you intend to use in play tests get WAY more academic and WAS less useful.

I agree completely. It would be 100% academic. The point would be to see if under, absolute, ideal conditions, if spin could be imparted on a paintball, and if so whether or not it would, actually, help. For example, if we were to take a projectile and prove that the barrel put spin on it, but also prove that it didn't effect accuracy, we could, absolutely, call the concept dead.

I see it in the same light that Myth Busters does many of their experiments. They first test the myth under "normal" conditions, to see if it's true, then they test it under ideal conditions, if it still doesn't work, they call it busted (and blow it up).

This post has been edited by Troy: 06 October 2012 - 05:39 AM

[rntlee]

It's much easier to test than that. Simply patch regular paintballs in a rifled barrel.

[The Dad]

brycelarson, on 01 October 2012 - 08:10 AM, said:

Troy, on 30 September 2012 - 12:47 PM, said:

You're on the right track... I hadn't thought of using rifling on reballs, but the problem is that the rifling on hammer head barrels is on the over bore section of the barrel, so the ball doesn't come into contact with the rifling, so it won't spin it.

yeah, and reballs are tiny - so they would have even less contact with the rifled portion of the barrel.

[The Dad]

I have been using a hammerhead barrel that is .084 and have found it to be more accurate than my .681, .678 smooth bores. Any ideas as to why?

[brycelarson]

The Dad, on 24 January 2013 - 01:28 AM, said:

I have been using a hammerhead barrel that is .084 and have found it to be more accurate than my .681, .678 smooth bores. Any ideas as to why?

Do you have data showing that it's more accurate? In general anecdotal perception is a poor measure of actual performance.

[The Dad]

No data, just observation which is part of scientific method. Maybe, I should say more consistant ball flight probably due to not underboring to much. Just curious as to why punkworks helped to make a barrel with boring sizes of .680, .685, .690 then called it an underbore, when most of their data seems to point to ball/ bore match or slight undersizing....
I really appreciate all the hard work that punkworks has put into paintball for those of us who are trying to learn more about paintballing and the are a great inspiration to those who want to be analytical in their pursuits.

[The Dad]

The above barrel kit GnB underbore barrel kit mentions your site as a collaborative effort in the making of these barrels..... Do you feel these are a better barrel than the rest and if so, is there data to support this.....

[brycelarson]

They didn't really go as far as we suggested but they based their design partially on our work. The Lurker barrels and the FLASC kits are actually the closest barrels on the market to our optimal barrel design.

We like:
Slight underbore - .003-.005
Long control bore - aprox. 9.5" is a good length.
Overbored tip with porting - total barrel length in the 14-16" range is best.

We were unable to repeat Hammerhead's results in our accuracy testing.

[The Dad]

Thanks for the information Bryce, I really enjoy reading all the postings and data that you have provided.

Thanks for the information Bryce, I really enjoy reading all the postings and data that you have provided.

[drg]

The Dad, on 24 January 2013 - 01:28 AM, said:

I have been using a hammerhead barrel that is .084 and have found it to be more accurate than my .681, .678 smooth bores. Any ideas as to why?

Placebo effect is assumed unless you have data that can be independently verified.

[The Dad]

Possibly or it could be that colder temps have an effect on the shell and it's contents, thereby allowing the rifling to engage the ball better. Has anyone done studies on the effects of temperature on paintballs, and flight. I do have more barrel breaks when underboring .078 with ..085

[Troy]

The Dad, on 24 January 2013 - 08:13 PM, said:

Possibly or it could be that colder temps have an effect on the shell and it's contents, thereby allowing the rifling to engage the ball better. Has anyone done studies on the effects of temperature on paintballs, and flight. I do have more barrel breaks when underboring .078 with ..085

Data or shins.

This post has been edited by Troy: 24 January 2013 - 09:34 PM

[cockerpunk]

lots of talk, no data

[brycelarson]

The Dad, on 24 January 2013 - 08:13 PM, said:

Possibly or it could be that colder temps have an effect on the shell and it's contents, thereby allowing the rifling to engage the ball better. Has anyone done studies on the effects of temperature on paintballs, and flight. I do have more barrel breaks when underboring .078 with ..085

So you're shooting .685 paint in a .678 barrel in the cold? Yeah, that sounds about right.