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Old 11-20-2012, 09:05 AM   #31 (permalink)
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There are SO many possibilities for this marker, Ill admit the DAM feels more refined, but the guys at good people.
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Old 11-20-2012, 09:30 AM   #32 (permalink)
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Misconceptions of paintball physics

These posts are interesting regarding both the magazines and FS projectiles. When we test we examine flight characteristics of both FS rounds and typical paintball rounds; however, when we advertise it is based on the FS rounds test results. To be completely blunt, all prior ballistic knowledge of standard .68 caliber paintball is of no value when evaluating the FS projectiles.

Lets look at two different barrel set ups on a typical marker. Both barrels are the same length of 16 inch, with same bore, and each barrel was fired from the same gun, with the same velocity. Which barrel will give better grouping and distance? Rifled, correct?

Findings: With the rifled barrel we found that the shot group tightened and we had less of a gun angle than typical smoothbore barrels. Less gun angle, or flatter trajectory means that the round, if leaving the barrel at the same velocity, must be sustaining its velocity down range. This efficiency is called Ballistic Coefficient. and as efficiency increases so does the ballistic coefficient.
These findings only added questions. For instance what is occurring to make this difference in flight.

When FS rounds escape from a smooth bore barrel there is an immediate deceleration force being applied to the fins (among other features). Because this projectile has mass, it takes both time and substantial energy to induce this angular velocity. Because energy is never lost, this would mean that the energy has been transferred from the projectiles forward momentum. This transfer of energy from the projectiles forward momentum to the angular acceleration is why the smooth bore barrel is not as efficient as the rifled. Slow motion video proves our theory

When FS leave from a rifled barrel, they already have the angular velocity imparted upon them. This makes them more efficient through flight because of the above paragraph; however there is one other item we can't forget about. By spinning a round nosed projectile, a contrail behind the projectile emerges. This contrail actually reduces drag on the back of the projectile.

20" barrel give the projectile more time to increase angular velocity, thus making it more efficient than the 16". Also this barrel, valve system was co-developed between HammerHead and Carmatech, so the markers efficiency is very impressive. On the 13/3000 hpa tank we have had reports of 180-200 shots. Its all about optimizing dwell, valve pressures, and valve volume.

Finally the magazine design. The reason for locking lifters is to reduce the time that the helical spring (lift spring) can impart energy on to the rounds. By our findings it seems that a typical paintball magazine can impart 1.125- 1.40 lbs of force when fully loaded. Just add humidity and now you have dimpled paint. Our design is different as ArchAngel and Gab have illustrated. We actually use a spring that is constant throughout its cycle and we have been able to reduce that force substantially. Less force no dimples, consistent feed into the breach.

Thanks
David Williams
Engineer
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Old 11-20-2012, 09:31 AM   #33 (permalink)
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Originally Posted by CarmatechEng View Post
These posts are interesting regarding both the magazines and FS projectiles. When we test we examine flight characteristics of both FS rounds and typical paintball rounds; however, when we advertise it is based on the FS rounds test results. To be completely blunt, all prior ballistic knowledge of standard .68 caliber paintball is of no value when evaluating the FS projectiles.

Lets look at two different barrel set ups on a typical marker. Both barrels are the same length of 16 inch, with same bore, and each barrel was fired from the same gun, with the same velocity. Which barrel will give better grouping and distance? Rifled, correct?

Findings: With the rifled barrel we found that the shot group tightened and we had less of a gun angle than typical smoothbore barrels. Less gun angle, or flatter trajectory means that the round, if leaving the barrel at the same velocity, must be sustaining its velocity down range. This efficiency is called Ballistic Coefficient. and as efficiency increases so does the ballistic coefficient.
These findings only added questions. For instance what is occurring to make this difference in flight.

When FS rounds escape from a smooth bore barrel there is an immediate deceleration force being applied to the fins (among other features). Because this projectile has mass, it takes both time and substantial energy to induce this angular velocity. Because energy is never lost, this would mean that the energy has been transferred from the projectiles forward momentum. This transfer of energy from the projectiles forward momentum to the angular acceleration is why the smooth bore barrel is not as efficient as the rifled. Slow motion video proves our theory

When FS leave from a rifled barrel, they already have the angular velocity imparted upon them. This makes them more efficient through flight because of the above paragraph; however there is one other item we can't forget about. By spinning a round nosed projectile, a contrail behind the projectile emerges. This contrail actually reduces drag on the back of the projectile.

20" barrel give the projectile more time to increase angular velocity, thus making it more efficient than the 16". Also this barrel, valve system was co-developed between HammerHead and Carmatech, so the markers efficiency is very impressive. On the 13/3000 hpa tank we have had reports of 180-200 shots. Its all about optimizing dwell, valve pressures, and valve volume.

Finally the magazine design. The reason for locking lifters is to reduce the time that the helical spring (lift spring) can impart energy on to the rounds. By our findings it seems that a typical paintball magazine can impart 1.125- 1.40 lbs of force when fully loaded. Just add humidity and now you have dimpled paint. Our design is different as ArchAngel and Gab have illustrated. We actually use a spring that is constant throughout its cycle and we have been able to reduce that force substantially. Less force no dimples, consistent feed into the breach.

Thanks
David Williams
Engineer
for regular rounds, my rifled barrel doesn't shoot any different from my straight ones, but the rest of your post makes sense, the other guy never specified what rounds you used.

and i think it should be pointed out that spiral rifling should be used for this effect. iirc there exists straight rifled barrels. hell, my armon barrel is even spiraled in the opposite direction...

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but the guys at good people.
but do they want to go do look more like?

Last edited by heinous; 11-20-2012 at 09:35 AM.
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Old 11-20-2012, 11:04 AM   #34 (permalink)
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Originally Posted by tangus999 View Post
thats a terrible way to do a test.
barrel could be cocked causing it to aim higher or lower depending on which barrel youd be refering to....

each barrel would need rezeroed and chronoed.

this is a new relm for paintball where the slitest difference makes a big difference and new thought processes similiar to firearms need to be brought into play.
^^^^THIS!!!!

Plus if the marker was being a "gas hog," wasting a bit of gas with the 14" barrel, the 20" barrel would be able to use that extra gas to propel the round, resulting in a higher velocity, explaining the higher hit. But there are no chrony numbers.....

I assume that, since they were really testing the effect of longer rifling on FS rounds, that they rezeroed the scope and readjusted velocity to the same as for 14" barrel (300 fps or lower, obviously, for it's intended use). Then you can say that the FS round had more angular momentum (spin) with the 20", carrying the FS round further, thus explaining the higher and longer shot.

We need to see the numbers man!
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Old 11-20-2012, 12:00 PM   #35 (permalink)
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With all possible respect, can you prove (or has anyone ever proven) that a "rifled" paintball barrel actually increases the gyroscopic spin rate of a First Strike round? I find these claims extremely dubious considering the fact that the lands and grooves in paintball barrels are not affecting air flow in a quantifable way or deforming the projectile one whit. I could see it if the finned section of a First Strike round was wider, and actually mated with a barrel's twist on the exit, but this is not the case. Heck, I could even see if it one claimed that an enormous bore barrel (.700") was optimal for these rounds, as it could allow them to initiate a spin while in the barrel, but I find it very difficult to believe that there's any quantifiable difference between a relatively close barrel match in a smooth bore barrel and a relatively close barrel match in a barrel with minimal "rifling" that is neither deforming the ball nor mating with the fins to impart gyroscopic spin.

We need TK to debunk this one with a glass barrel and a high speed camera...
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Last edited by Riddler; 11-20-2012 at 12:07 PM.
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Old 11-20-2012, 01:55 PM   #36 (permalink)
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hummmm let's say that, if i make a video of a shoot with several barrel

the 20inch HH (rifled )
the bangstixx HH ( rifled )
the widow maker HH ( rifled )
lacpo 14"

That would pleased you ? ( with same FPS range -/+ 5 ) and laser on target ?

I should have my SAR12 beta in a couple of week. So time to make the shoot and the video editing.
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Old 11-20-2012, 02:09 PM   #37 (permalink)
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A high-speed video of exit spin rate from different barrels would be ideal, but lacking that, a bench-mounted test in which FS rounds are fired from different barrels, chronoing each shot and adjusting velocity as needed each time a barrel is changed, at a target 225' away, as per the purported test referenced above, would be at least something empirical.
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Old 11-20-2012, 04:28 PM   #38 (permalink)
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Originally Posted by Riddler View Post
A high-speed video of exit spin rate from different barrels would be ideal, but lacking that, a bench-mounted test in which FS rounds are fired from different barrels, chronoing each shot and adjusting velocity as needed each time a barrel is changed, at a target 225' away, as per the purported test referenced above, would be at least something empirical.
Sorry don't have a 43 000$ camera to do so
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Old 11-20-2012, 06:08 PM   #39 (permalink)
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Originally Posted by Riddler View Post
With all possible respect, can you prove (or has anyone ever proven) that a "rifled" paintball barrel actually increases the gyroscopic spin rate of a First Strike round? I find these claims extremely dubious considering the fact that the lands and grooves in paintball barrels are not affecting air flow in a quantifable way or deforming the projectile one whit. I could see it if the finned section of a First Strike round was wider, and actually mated with a barrel's twist on the exit, but this is not the case. Heck, I could even see if it one claimed that an enormous bore barrel (.700") was optimal for these rounds, as it could allow them to initiate a spin while in the barrel, but I find it very difficult to believe that there's any quantifiable difference between a relatively close barrel match in a smooth bore barrel and a relatively close barrel match in a barrel with minimal "rifling" that is neither deforming the ball nor mating with the fins to impart gyroscopic spin.

We need TK to debunk this one with a glass barrel and a high speed camera...
I don't think we need to go that far. If the rifling of the barrel contacts the projectile it will impart spin. End of story.

How much spin? I don't know.

Is the spin beneficial? Well, there is kinetic energy stored in spin which means at a given velocity a spinning projectile should travel farther than an identical non-spinning projectile.

How much spin is optimal? I don't know.
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Old 11-20-2012, 08:24 PM   #40 (permalink)
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Originally Posted by Riddler View Post
With all possible respect, can you prove (or has anyone ever proven) that a "rifled" paintball barrel actually increases the gyroscopic spin rate of a First Strike round? I find these claims extremely dubious considering the fact that the lands and grooves in paintball barrels are not affecting air flow in a quantifable way or deforming the projectile one whit. I could see it if the finned section of a First Strike round was wider, and actually mated with a barrel's twist on the exit, but this is not the case. Heck, I could even see if it one claimed that an enormous bore barrel (.700") was optimal for these rounds, as it could allow them to initiate a spin while in the barrel, but I find it very difficult to believe that there's any quantifiable difference between a relatively close barrel match in a smooth bore barrel and a relatively close barrel match in a barrel with minimal "rifling" that is neither deforming the ball nor mating with the fins to impart gyroscopic spin.

We need TK to debunk this one with a glass barrel and a high speed camera...
there was another test done by another member here testing the effectiveness of rifled barrels with FS rounds. He took pics of the groupings and the rifled barrel groupings were quite a bit tighter than the smooth bore barrel's. I'll link it when i find it lol

edit:
Shot results: New Tiberius Rifled barrel vs Stock barrel
Theres a lot of discussion about rifled barrels+fs rounds if u know where to find it.

Last edited by -=ArchAngel=-; 11-20-2012 at 08:32 PM.
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