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Accuracy, Never Enough to Go Around


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#1 Whiskey Hammer

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Posted 31 March 2014 - 02:22 PM

We've completed not one but two rounds of accuracy testing and we've hit a bit of an obstacle. Initially, I wanted to have the data out in a "one or two week" timeline from the posting date but, for reasons we'll get into below, I'm not comfortable releasing it yet.

 

The problem in my accuracy tests, is accuracy. I'm not getting as much as I should be getting. Take a look at the below comparison of X-component deviation* in the baseline groups from Punkworks and our first shooting session. Punkworks is getting a final result that is more than twice as accurate.

  • Punkworks: 1.725 inches
  • First Round: 3.6 inches

Obviously I was missing something... I came across the FS Centrifuge post on M. Carter Brown and I thought that it was a very likely explanation for my accuracy problem. The paint in bulk boxes doesn't sit uniformly so the asymmetric mass distribution of odd settled paint throws off the accuracy. Seems legit right? I grabbed a round and forcefully tapped it against a level surface to settle the paint against the nose of the round. Along the same lines of how you would force a bottle of ketchup to settle at the spout. I visually inspected the round and the paint seemed to be pretty uniformly settled in the nose. To be safe I allowed the rounds to sit nose down overnight before the next round of testing and re-tapped them before firing. The comparison between Punkworks, the first round, and the second round is below.

  • Punkworks: 1.725 inches
  • First Round: 3.6 inches
  • Second Round: 3.55 inches

No statistically important difference. I racked my brain trying to explain the difference, and while looking at the 8 shot group distinctions in the Punkworks data set, I remembered that their methodology artificially centered each magazine's group. It follows then that the normalizing might also have a damping effect on the natural randomness of the rounds. The most likely way they did this was to average each groups X and Y values, and then subtract that average from the actual values. This results in three groups whose average values (i.e. centers) are all at the same (0,0) point.

 

Edit: Ha, I knew I remeber seeing a video about this: Tiberius First Strike Test Thoughts by cockerpunk. It touches on the damping effect that correcting the groups has.

 

I applied (ostensibly) (confirmed) the same mathematical methodology to my groups and it made a difference. We got about an inch off the group, which is pretty significant. Definitely closing the gap but certainly not all the way there.

  • Punkworks: 1.725 inches
  • First/Second Rounds: approx. 2.6 inches

Now we just need to shore up that last inch.

 

Thinking about it some more, it could be the barrel setup. There is a short stretch of smoothbore before the rifling in my MR5 setup that could be throwing off the accuracy. We know that smoothbores don't do much to the spin of the round;  in some cases it can even rotate in the wrong direction. It's possible that the smoothbore presection is allowing some rounds to get a counterproductive spin before they hit the rifling and that those rounds aren't being stabilized as well as they otherwise would be.

 

It could also just be that my paint settling methodology didn't work as well as long-term nose down or centrifugally settled paint. I might have just grabbed and visually inspected a couple of rounds that were naturally settled right.

 

Another possibility is that I'm botching something about the mathematical theory here.

 

So basically I need to shoot a group that has been centrifugally settled, shoot a group from a system that doesn't have the smoothbore presection, and mess with the numbers more/shoot a larger group size/get confirmation on the Punkworks math.

 

Once I figure out what's going on with my accuracy I'll feel batter tackling my 121 accuracy/drag data.

 

The issue going forward is money. It's a finite resource for most of us, and I definitely include myself in that number. It would be a serious kick in the dick to shell out money for the only tested rifled barrel that works natively with the MR5. That would of course be the Hammer 7 threaded Tiberius/Lapco barrel. The other less dick kickish option is to buy the threaded Hammerhead back for Ion/Impulse threads and do a test group on my Ion. There are a couple of concerns there but it's a decent solution from a trouble shooting standpoint. Anybody have the Lapco barrel or a Hammerhead back in Ion/Impulse they'd be willing to loan out? I'd of course be willing to put up collateral through a third-party for the full replacement value. I can float the money easy as pie, but I'd rather avoid sinking it when I need to restock my paint. Other than that, I'm gonna move some gear on craigslist and buy paint as sales allow.

 

Oh and the studio/warehouse owner shot some behind the scenes stuff when we did our first shooting session. Bro did it gratis and I think it turned out pretty cool. Check it out here.

 

*I prefer to compare accuracy using just the X-component rather than the vector. I'll get into the specifc reasoning in another this post, but for now bear with me.


Edited by Whiskey Hammer, 01 April 2014 - 05:48 PM.


#2 andrewthewookie

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Posted 31 March 2014 - 04:15 PM

Are you pulling Punkworks numbers from the original test, or from the more recent rifled barrel test?

 

Even with all that, it could just be inconsistency of manufacturing process. The original testing was done nearly 5 years ago, more or less when the rounds came out. During that time they could have made some changes to the process that could have these effects.


Edited by andrewthewookie, 31 March 2014 - 04:20 PM.

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#3 UV Halo

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Posted 31 March 2014 - 07:00 PM

Even with all that, it could just be inconsistency of manufacturing process. The original testing was done nearly 5 years ago, more or less when the rounds came out. During that time they could have made some changes to the process that could have these effects.

 

Actually, the original smoothbore test was done a long time ago.  The rifled test was just over a year ago.



#4 UV Halo

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Posted 31 March 2014 - 07:07 PM

Bryce or Cockerpunk didn't do any pre-treatment of the rounds and the rifled barrel accuracy test was done with rounds straight out of the box (which I provided).  So, I'd scratch that out as being a contributor.
 
As for the Vector comparison, I prefer it because it best represents spread in two dimensions (which all of our projectiles do, even with a very high velocity consistency).  The only thing I can think of that it would't represent well would be vertical stringing but, I can't say that I've seen anything like that which couldn't be attributed to serious velocity consistency problems.  The only other 'measurement' I would go for would be 'absolute spread' measured and reported in the same way as firearms but, with a larger sample size (since our projectiles are so much worse than a firearm).
 
If you can, it might be helpful to post the raw data (impact locations, velocities, etc).
 
You could also post more details on your testing platform since, this was your first go-round, Bryce or Cockerpunk may have some feedback for you there.


#5 cockerpunk

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Posted 31 March 2014 - 07:50 PM

when we start to get really low in terms of vectors, its hard to judge relivence. with our standard measurement resolution of only 1 inch, its tough to argue about the difference in a vector of below a half an inch, and again, we were shooting short samples (only 8 instead of 20+). remember, when we first used this metric, we were looking at vectors mostly above 5 inches, so the signal to noise if you will was much better.

the frist test was done with rounds from there "test tubes" as they were sold at first.


The ultimate truth in paintball is that the interaction between the gun and the player is far and away the largest factor in accuracy, consistency, and reliability.

And yes, Gordon is the sexiest manifestation of "to the front."


#6 Whiskey Hammer

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Posted 01 April 2014 - 04:33 PM

The numbers are the average of the rifled barrel tests for the Lapco and the Hammerhead. My posted numbers are averages for the entirety of each test. The first thing I tested was the manufacturing consistency with a sample size of 500+. It's over here. Comparing it the previous works on the subject, my data suggests that the manufacturing process, on the ammo end, has actually improved. it's possible that the barrels have gotten poorer. The twist rate is too slow and the length too short to reliably measure using conventional firearms methodologies (rotating handle barrel patch).

 

I dont think the data will be too useful at this point. There's a lot going on in terms of variables and refinement between the tests but, I'll put out a rough set of sheets later today or tomorrow. I have a lot of annotations and qualifications to make in the data so that they make proper sense, but I'm out in Daytona Beach picking up some machining equipment (lathes, mills, and hydraulic rams oh my! - I'm tooling up for some experiments with .300 BLK) and I wont be back till late. For now I'm just sitting out rush hour traffic.   

 

In related news, I drank too much cofeee yesterday afternoon and couldnt sleep last night. So what I did do was jot up my argument for favoring the x-component. I'll post it after this over here.

 

In terms of the platform, it's an unmodifed spyder MR5. I've rigged it to run on a palmers stab (as you can see in the "behind the scense" pics). The MR5 uses a method of barrel attachment simialr to the T8x/T9x series of markers and hammerhead doesnt stock a back for it. The MR5 did however come with an early run of a standard threaded barrel adapter, so I'm using it with that. That's where my concern for the smoothbore presection comes from. In addition to that I'm firing the marker upside down, and clamped to mobile contruction table/clamp setup. It's stable and super conveinent for firing - I cut the bottom off of the mag, and feed the rounds in hopper-style now. It's way faster to run the tests and I dont have the shifting POA problem.

 

In the first round of tests we measured in CMs out to roughly 0.1 resolution. That took way too long however, so I went out and bought one of those vinyl DND battle mats. It's a premade 30x40 inch grid that makes assesing the rounds (and cleaning up afterward) super easy and fast. This we measured out a rough 0.1 resoultion. I ran the numbers though, and the extra resolution doesnt add anything to the final SD calculation, so next time well just go for a resolution of  1 or 0.5 inches.

 

I did look over my first round of data today though and there was one outlier. When I shot my first baseline group with the first round of testing, I got an x-component SD of 2.48, which when accounting for the mathematical centering actually beats the Punkworks value. At the time, I thought the value was kinda crazy so I ran it again to be sure - I wasnt able to reproduce it. Thinking about it, I explicitly recall grabbing only rounds that were nose down at the top of the bulk box. It was easier to extract the rounds by just clamping the skirts with my fingertips. It's possible that I grabbed a bunch of rounds that were naturally settled nose down for that one test. I think it's even more likely considering that punkworks shot thier rounds from the old stacked tubes.


Edited by Whiskey Hammer, 01 April 2014 - 05:12 PM.


#7 Whiskey Hammer

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Posted 07 April 2014 - 04:49 PM

And... heres the rough cut of the data. Be sure to look at the below before you dive in.

 

In the first round, my process with the variables was to create a baseline using a speculative "most accurate" combination of factors and then test each factor one at a time, while the others remain constant with the baseline. In the second round, I wanted the test to be more "apples to apples" with the Punkworks test so that the two sets could be readily compared or used together. Hence the difference in variable schema between the first and second round. 

 

The chrono in the first few groupings of the second test was malfunctioning due to a dying battery. Those cells have been highlighted in a darker orange. The battery was replaced, and the reading became more reasonable and consistent with previous testing. 

 

The rigid variable test group in the second test suffered from a shifting POA every four shots due to operator error. The groups are seperated by dashed lines. I might artificaily center them later (or let someone with excel skills take care of it). Edit: I ran the numbers and unsurprisingly the more groups you break a population into, the more exaggerated the corrective effect of the mathematical centering.

 

Some quick notes on the variable terminology:

  • Rigid vs Free-Float: whether or not the barrel was braced against the edge of the firing bench/clamp to pretension the barrel and prevent flexing. 
  • Unsorted/Ratioed vs Sorted: whether or not the ammo lot was sorted to size. If the ammo was unsorted it was still made to reflect the size ratios found in the Manufacturing Consistency phase of the test. 
  • Untapped vs Tapped: whether or not an attempt was made to settle the paint into the nose of the round by a forcefull tapping.
  • Tipless vs Tip: whether or not the barrel had the factory tip during firing. 

Edited by Whiskey Hammer, 23 September 2014 - 01:17 PM.


#8 UV Halo

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Posted 08 April 2014 - 12:56 PM

Thanks for sharing!

 

I can't really read it too well now (crappy browser) but, I'll give it a thorough once over (to include crunching the vectors) later tonight.

 

Also, to be clear, the rifled barrel test conducted by Punkworks used paint from the bulk 100rd box and not the tubes.  It was an all in one test, that included my T9.1, Stock, and LAPCO Smoothbore barrels, as well as the LAPCO/Tiberius Rifled Barrels and the Hammerhead.  They were also able to shoot all of the shots n one go without recentering the rounds.

 

As for now, I suspect a barrel difference between the T9.1 Punkworks test and your gun.  Am I correct in understanding that you're using a clamped down MR5 with a spyder threaded hammerheaded barrel connected to the MR5 by a barrel adapter?  If so, which hammerhead barrel?



#9 cockerpunk

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Posted 08 April 2014 - 01:20 PM

i would recommend and comment that any kind of sorting, or such to the paint before firing, while interesting scientifically, isn't really how these things are used, so do not reflect real world performance. even things like the bracing of the barrel you talk about, again, thats not the way these markers are used either, so again, its not really showing real world effects then.


The ultimate truth in paintball is that the interaction between the gun and the player is far and away the largest factor in accuracy, consistency, and reliability.

And yes, Gordon is the sexiest manifestation of "to the front."


#10 UV Halo

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Posted 08 April 2014 - 02:01 PM

i would recommend and comment that any kind of sorting, or such to the paint before firing, while interesting scientifically, isn't really how these things are used, so do not reflect real world performance. even things like the bracing of the barrel you talk about, again, thats not the way these markers are used either, so again, its not really showing real world effects then.

 

While it's certainly not mainstream to sort FS rounds, I've run into several and know of more folks via the internet that do things like store the rounds upright, and pre-sort them, in the hopes of attaining maximum accuracy.  Unfortunately, up until now, there was no published data to prove whether or not these things make a difference.  If it proves to be effective, even more folks will adopt the practice.  That being said, there's more data to be collected.  For example, if it turns out that storing the paint nose down makes them more accurate, then it follows to investigate how long must they be stored nose down and, how long in another position before you lose the benefit?  If it turns out that the benefit is lost in as few as five minutes, I personally would find it pointless.



#11 Whiskey Hammer

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Posted 08 April 2014 - 08:54 PM

Whoops, I misunderstood. Cockerpunk deliberatly wrote "first test." My focus on rifled barrels led to mental tunnel vision and I forgot about the series of smoothbore accuracy tests (seriously though, it's happend two or three times now). Duly noted. In that case, I agree that it's less likely to be caused by poorly settled paint and more likely to be casued by my barrel setup. I've got some community members sending me gear to help troubleshoot, so I'll run a confirmation test as soon as it all gets in. [Edit: it does however get me excited for the possible effects of nose settled ammo]

 

And uv_halo nailed. It's more about finding out what the system is capable of than what the system is for the average player. With the caveat that the final analysis and any recommendations will center around those techniques that can be ready utilized by the average player.

 

Also, if it turns out that nose settled paint is only viable for 5 minutes, then somebody somewhere will put together a nose-down top-mounted pan magazine fed marker to milk that benefit. Kinda like the Lewis MG. Actually, that could look pretty bad ass. Or tube holders deliberatly designed to store the ammo point down on the chest, that you can pull out like one of those old school arcade coin belts (for use with single shot bolt actions). Where there's performance to be had...  


Edited by Whiskey Hammer, 14 April 2014 - 12:43 PM.


#12 UV Halo

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Posted 08 April 2014 - 08:58 PM

Okay, So, I've given the data a once over and I've calculated the vector values for all of the groups.  Thank you very much for the excellent data, and taking the time and resources to do the test.

 

The Vector Values for most of them are in the ballpark for the LAPCO/Tiberius 9" (4.8") so, that covers all of them except the:

  • Baseline 2, Sorted, Large (6.20)
  • Round 2 Rigid (uncorrected)*

and maybe Baseline 2 (5.63) and the Highspeed (5.64) datasets if someone stronger in statistics can confirm that those are in or out of line with the 4.8" values.

 

I'm not sure what's up with the Baseline 2, Sorted, Large data.  The larger rounds were also slightly heavier so, I wouldn't expect a significant change there froma drag perspective.

 

* As for the Rigid (uncorrected) data, it came in at 3.69 which would be the best however, I suspect that the smaller (4 shot) sample size may have skewed the group, like you and Cockerpunk mentioned for the initial (pre-rifled) FS test data.

 

So, my questions going forward are:

 

What was the Test barrel?  You mentioned Hammerhead but to the best of my knowledge, Hammerhead doesn't make a spyder threaded one piece barrel.  If you were using one with a fin, and the Spyder adapter, that adds up toa several inches of un-rifled length in which the ball is allowed to get to a high speed before engaging the relatively loose hammerhead rifling.

 

Was the barrel cleaned between any of the test sets?  In the Punkworks rifled barrel test, they were using completely different barrels from set to set so, there was never an opportunity for buildup to occur.

 

Was the "Highspeed" test labled such because of the average velocity or, because you also recorded HSV of it as well?

 

Can you share the HSV showing the barrel movement?



#13 Whiskey Hammer

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Posted 09 April 2014 - 01:55 PM

With regards to the Second Round Rigid test: the smaller the groups you use for the correction, the more pronounced the effect. I'm just gonna ignore that whole grouping. There's no way to tell what the real accuracy would have been and we cant compare it directly to the Punkworks data beacuse the splits are so different.

 

What was the Test barrel?  You mentioned Hammerhead but to the best of my knowledge, Hammerhead doesn't make a spyder threaded one piece barrel.  If you were using one with a fin, and the Spyder adapter, that adds up toa several inches of un-rifled length in which the ball is allowed to get to a high speed before engaging the relatively loose hammerhead rifling.

 

Exactly my concern. The test barrel was the Hammerhead Mofo Scenario with a .686 back. The final assembly goes, adapter, fin/back, barrel.

 

In the first round of testing, barrels were swabbed every other grouping. In the Second round, they were swabbed after every grouping. The build up was never visually noticable down the bore or on the swab in either test.

 

The highspeed test rounds were shot at deliberatly high chrono speeds in an attempt to artififically increase thier rotational velocity. I say attempt because its possible that the higher speeds just gave the round more incentive to slip the rifling. We know (thank you uv-halo) that nearly all of the manufacturers use barrels that were originally designed for use with spherical ammunition back in the heady days of 90s paintball experimentation. They were junk with spherical rounds and the people who sold them did so unethically. But by a stroke of moral luck, first strikes appeared and greatly benefitted from the extra spin of these barrels. These barrels' twist is about 1:52. Thats really really slow. Whats worse is that we know there is slippage in the barrel (from the punkworks rifled barrel test), so the rounds dont even reach the relatively tame rotational velocity that a 1:52 twist at 300fps should acheive. Between the ultra slow twist and the in-barrel slippage, I theorize that the rounds would stand to benefit from a faster spin. 

 

The idea was to shoot the rounds at a higher velocity, thus raising thier rate of spin, then using the dual chrono data, correct the final grouping to account for the shorter flight path and see what the faster spin does for the accuracy performance of the rounds. We still need to shoot the dual chrono and we still need to dial in our accuracy problems to get a clearer signal before we can say conclusively one way or the other, but even then we could still see no improvement if the extra kick of the rounds and the relatively loose rifling of the hammerhead just end up making the round slip more. This might be a test better suited for the Tiberius/Lapco.

 

Or Punkworks... I originally had the HSV camera to measure the rotational velocity (and therefore slippage / consistency) as the rounds leave the bore, but my photographer backed out last second and I never got a quality useable video. If you guys still have access to the camera then it might make for a good test. 

 

I still have the HSV of the barrel flex (the inspiration for the rigid barrel variable). I'll have a buddy put together a video out of them. The vapor/vortexes out of the muzzle are pretty wicked too. Edit: Or not. Heres a quickie thrown together with youtube's native editor. High Speed Barrel Flex.

 

Also, I did some bonus work on the raw cut of the data. I corrected the groupings for the rigid barrel (just to see what it would look like) and added quick-refernce/comparison sheet with all the standard deviations and the vector. But for the record, the x-component is where its at. 


Edited by Whiskey Hammer, 09 April 2014 - 03:35 PM.


#14 Whiskey Hammer

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Posted 09 April 2014 - 03:38 PM

Video Up: High Speed Barrel Flex



#15 UV Halo

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Posted 09 April 2014 - 09:58 PM

Very Cool, Thanks for the HSV!  At first glance, it's clear that the barrel does shake but, it appears to happen very little if at all before the round leaves.  How many Frames/sec was that?

 

I believe that your barrel, or more specifically, the adapter and fin combo, reduced the performance of the rifling.  In a couple months we can discuss me sending you my T9.1 (and multiple barrels) for testing.

 

As for rifling, I believe the fins have a higher rate of twist relative to the barrel because, air slips over the fins.  It'd be interesting to see how barrels with different rifling rates would affect FS rounds.

 

Given what Cockerpunk and you said in regards to 'signal to noise', and my own observations, it may be worth moving FS round testing to further distances.  Maybe 100ft?  But, I still believe that it needs to be done indoors, things certainly don't get easier :-/

 

I respectfully disagree with the X value mattering more :P



#16 Whiskey Hammer

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Posted 11 April 2014 - 10:49 AM

The frame rate was 1200fps. Its the same camera used by Punkworks for their slowmo vids - the Casio EX F1. Its an inexpensive quality highspeed camera (at least relative to other high speeds) so its not tough to find at good rental prices.

 

I slowed the video down to half speed to watch it better. The barrel flexs upward as the ball travels down the barrel, then exits. The barrel then snaps back down, and combined with the violent reciprocation and locking of the action, ends up whipping around some more. The barrel does not visibly flex when braced.

 

The signal to noise probably wont be an issue once we get the accuracy sorted out. Right now it's possible that the confounding variables (noise) of the barrel are drowning out any improvements in accuracy from our test variables (signal). The only time wed need to push the distance out more was if our baseline was so good that any improvement in accuracy wouldnt be apparent. For example, we fix the barrel and get accuracy down to 2.5 x-SD (which, based on the math, is about what I'm expecting), then we find out that centrifuged ammo brings that down to (practically) ball-on-ball accuracy at 75ft, then we find out that rigid barrels also bring it down to ball on ball. If we wanted to test the accuracy of a barrel that is both rigid and shooting centrifuged ammo, wed probbaly need to push the distances out since we wouldnt have any room to observe improvement. 

 

And your absoultely right about indoor sapces being tough to find, especially the larger your test distance grows. I contacted every indoor paintball and airsoft field in the north half of Florida. It was not an encourgaing experience. Thats when I bit the bullet and started putting cash up for the spaces, the cheapest and best customer service was, by far, the indoor photography studios. They're used to dealing with crazy artsy types throwing paint and nude ladies everywhere so paintball was breeze. It might be less of a problem up north where indoor paintball is more common, but here in the sub-tropical south, the pickings are slim. 


Edited by Whiskey Hammer, 11 April 2014 - 11:32 AM.


#17 brycelarson

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Posted 11 April 2014 - 12:34 PM

quality work so far.  love to see where you end up.



#18 Whiskey Hammer

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Posted 11 May 2014 - 06:38 PM

News on the trouble shooting front. I ran a test last Wednesday, and eliminating the smoothbore presection helped accuracy (or it could be that closed bolts are naturally more accurate, but this seems less likely). The problem remains that we're still no where near the right level of accuracy even after getting a very minor boost from artificially centering three groups of eight. At this point I think I might just have a bum HH barrel. Before running out of the door for a game in Tampa this weekend, I looked down the barrel and saw what appeared to be slight hill in the bore. Similar to what you might expect the negative side of a ding to look like. There wasnt a a corresponding ding on the outside of the barrel though. Once I'm back in jax, Ill take another look to confirm, but I'm fairly certain there was slight bump in the bore (a manufacturing error maybe?) and that it might be whats frustrating my accuracy.

 

In related news, I also tested centrifuged rounds. Turns out that they are more accurate than plain jane rounds. My impact plot data for that test was messed up, so I dont have hard standard deviations, but what I do have is the ability to compare downfield chrono sweetspots.

 

Edit: I also fixed my chrono problems. If you recall, I suspected that the light source I used was washing out the chrono's ability to detect peripheral passes. I bought some rope light and stretched them across the plastic light diffuser that sits above the eyes, and got much better sensitivity. 

 

Basically there is a trapezoid area above each eye of the chrono, that a round has to pass through in order to properly register at that eye. The machine counts the amount of time that passes between each register and calculates the speed from that. If the round goes through the chrono but is outside both of these areas, then you wont get a read (referred to later as a 'no-read'). If it passes through the first trapezoid, but not the other, then you get an 'error' reading. In the plain jane test, I got several 'no-reads' and one or 'two errors'. This means that a lot of rounds were so wild that the chrono was essentially blind to them, and at least a couple that were less wild but still bad enough the the chrono had no idea how fast they were going. The centrifuged rounds, had one 'error' reading and no 'no-reads'. No hard vector based standard deviation, but still more accurate.

Edit: For the sake of completeness, the data was recorded but it was very rushed and I’m not confident that I didnt switch some of the positive/negative signs in my haste. I caught myself doing it once or twice and needless to say, this is something that can inflate the final standard deviation. I’ve added this third run to the previous spreadsheet.


Edited by Whiskey Hammer, 23 September 2014 - 01:14 PM.


#19 XGC_Cheevo

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Posted 12 May 2014 - 11:55 AM

Were you testing centrifuged FS rounds or centrifuged regular rounds?  Like if you had a purple/white shell ball and settled the paint on the purple side of the shell.  Are you loading them a certain way at that point?  Like white shell or purple shell up/down, forward back?  Maybe I'm off on my thinking of what you mean.



#20 PREDATOR 47

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Posted 12 May 2014 - 06:38 PM

I would assume FS. From what I've seen on MCB, the goal is to orient the paint towards the nose of the round.



#21 XGC_Cheevo

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Posted 12 May 2014 - 08:11 PM

Alright, yea I read the post from MCB on forcing the paint fronwards.  Like setting the FSR tubes upright and such.  I was just wondering if in this case the OP was actually paying attention to what orientation even regular balls were in, which while its no where even close to how paintballs perform in the real world, it is interesting if it makes a difference.



#22 Whiskey Hammer

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Posted 14 May 2014 - 01:28 PM

My testing is focused specifically on FS rounds from rifled barrels... Im not sure what effect centrifuging regular paint would have but, speculatively, it probably wouldnt be good.
 
In related news I think I found the culprit:
 
20140513_190659.jpg
 
20140513_190722.jpg
 
20140513_190733.jpg
 
I usually check bores from the chamber end and this bore defect is small enough that you’d only ever notice it if you were holding the barrel at the right angle to a bright light source while looking down the muzzle. Something I dont do as a matter of habit, and something I only did as a matter of expediency. It sits very close to the muzzle of the barrel and is probably not doing my accuracy any good. I’ve emailed Hammerhead, so hopefully well be able to get it switched out and tested soon.


Edited by Whiskey Hammer, 23 September 2014 - 01:12 PM.


#23 Whiskey Hammer

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Posted 22 August 2014 - 08:34 AM

Lack of updates right? Well I lost my shooting space. The good news is that Hammerhead sent a new barrel.
 
Once my replacement made it in, I called up Bubble Wrap only to find that they had just finishing moving to a new space. Cleaner, brighter, taller ceilings! Great for photographers. But just a bit under 50 feet at it’s widest. Bad for me. That essentially put me in shooting range homeless limbo.
 
I know I’ve mentioned it elsewhere but finding indoor spaces in the sub-tropical south is a nightmare. Indoor sports arent really a big thing down here, on account of it never getting that cold, and even when you do find a space big enough, you still have to talk the owners into letting you shoot things inside it. I spent about a month searching with nothing to show for it. I almost scored an office complex with a long hallway, but the building owner was (understandably) skittish about his windows. On a lark I re-emailed the local hack space JaxHax. Previously, they had showed interest in the project but for reasons I cant remember, they weren’t suitable at the time. But as luck would have it, they just purchased a second story in the multi-level warehouse complex they occupied. A very large first floor space with over 100 feet of clean and clear linear distance. KO.
 
The best part is, the price they were willing to let me shoot for. My photography studio had charged $50 an hour, which compared to other hourly studio rates, is a bargain. JaxHax was willing to let me have unlimited 24 hour access for the breath taking price of $75 a month. Perfect KO.
 
I’ve been getting the tests moving again and I cant tell you how sweet it is there. The lack of time pressure and hard deadlines makes everything so easy and convenient that I cant explain all the ways it manifests into an improved data product.
 
But, more to the point. A few days ago I completed what I consider to be a near perfect testing run with the new barrel and I can safely say that my previous accuracy troubles were barrel based. I wont get into the final numbers yet, since the test is ongoing, but there are already some interesting accuracy implications about manufacturing quality OR closed bolt markers. Since it was the only apparent flaw in the barrel, I feel confident that the micro-minuscule bump near the crown of the muzzle was my issue. I’ll write more about it at some point, but I’m more than a little miffed with Hammer Head at the moment. That bad barrel cost me several hundred FS rounds to diagnose.
 
Anyway, testing is live again. And just to titillate a bit more, our first session yielded some solid dual chrono numbers for rifled barrels. Mmmmm, impending BC answers…..

Edited by Whiskey Hammer, 23 September 2014 - 01:10 PM.


#24 Whiskey Hammer

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Posted 23 September 2014 - 01:41 PM

This should be the final trouble shooting update. After confirming that the barrel was my main accuracy problem. I set about testing different markers, the Empire Tracer worked great but for some reason, the velocity on my MR5 wouldnt go higher than 260. Obviously, I cant test with that. Figuring I’d hand load the rounds into the barrel, I switched to my old school Ion, but for some reason the board was malfunctioning and it wouldn’t let me shoot with the eyes off (and yes, I was using a fresh battery). A couple of other guns in my inventory later and I still hadn’t found a suitable shooter.
 
At this point, I figured I’d have to buy a new gun to get the test moving in a timely fashion. After putting some feelers out on craigslist I found a pawnshop had listed an old Spyder clone for the paltry sum of $30. I snapped it up figuring I’d make modifications to it to get it running up to spec. Imagine my surprise to find that the Spyder is just about perfect out of the box. Its one of the older half-tank breeds with flat sided heavy duty frame, meaning that I can clamp the ever living shit out of it for great stability. The feed neck slides off the frame and allows me to easily load FS rounds directly into the breech – no further milling or dremeling needed. Finally, as an added bonus the bolt has a groove in the nose that perfectly held an oring after the ball detent was removed, and now the gun is obnoxiously efficient. In short an unexpected unicorn.





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