Just came off the field looking for info to help me with some inaccuracy issues. I had a feeling this was the case but its great to hear this. Ill be changing barrels next sunday!
Wow! I'm sorry to have missed your post! My pleasure, and my extreme thanks to you for all the work you did. You made a profound contribution to the science of the sport, and you should know how much it is appreciated.
Great video. Found this out around 2006 after trial and error with all of the bore combinations. The reduced breach pressure from overboring also reduces barrel breaks which at the end of the day will keep more accurate shots all day. When the Ego first released, it quickly became notorious for not breaking paint and also shipped stock with a large .693 barrel.
Good video. When you crunched the numbers did you include our extreme underbore data? We were proponents of moderate underboring. We were aware that extreme underboring started making things go funky. We were aware of the correlation between overboring and potential accuracy increases. The reason we stuck to the underboring advice was twofold. 1. To get a situation were every ball was significantly overbored means shooting a GIANT barrel or risk accidentally paint matching. 2. The scale of the accuracy increase was so small that we felt the efficiency and consistency benefits of moderate underboing outweighed it. I like your theory that the greasy marbs were more forgiving on the underboring. Nice work, it's great to see people still talking about this.
Bryce, thank you, and nice to hear from you outside of MCB. :-) Welcome to the channel! To your question, I did indeed include that data, and mention it specifically around 14:05. As for your data, many of the old links were broken but Gordon was kind enough to send fresh links to the pertinent stuff. As noted in the video, I was thoroughly surprised by some of the findings of this meta-analysis (though you are right to note that in many cases, we are talking about pretty small differences, lest people root too loudly for their pet configuration). In any case, your work not only made it meaningful, but probably served as the Rosetta Stone for much of the rest of the data owing to its thoroughness. I really hope you know how important your undertaking was and is, and how much appreciated by those of us who can see it for what it is. The sport owes you guys a great debt. This channel salutes you.
Can you please clarify how much of an overbore is recommended? In other words, if the paint size is .685, should we be going with .687? .689? Etc. thank you for the very helpful video!
My pleasure, and thanks for the question! I don't think there's a magic number. The data suggests that a consistent overbore (so a bore through which all paintballs will consistently fall) will be optimal. So to your scenario, a .689 should work well enough. Remember that even in the best case, we are still talking about an inherently inaccurate projectile.
Wonderful videos. I enjoyed the whole series. I know from watching other videos that Simon Stevens recommends under boring. Has he ever commented on spin induced by under boring?
Thanks for weighing in, and for the kind words! Glad to know these are helpful. Simon is a wealth of knowledge, and his word carries a lot of weight in my book, as it should with everyone in this sport. He's a titan, and a gentleman on and off the field. While I've not not talked to him about underbore-induced spin specifically, he does advocate underboring, and he has a lot of data to support that position. Remember that he is coming from, and thinking about, a competitive perspective, where velocity consistency, and being able to run close to the upper register without fear of going over, are major concerns. He is also emphasizing the autococker platform, where underboring is a functional necessity (in my estimation). Remember also that paint is king, and the accuracy differences rendered by boring configurations, while real, are still relatively small. With that in mind, underboring with good paint in any marker is not going to make or break the bank, and if it prevents a hot gun penalty, it may help far more than hurt. And in an autococker, it is essential for competitive play. Bear in mind also that tradeoffs are always involved, so different experts in the field may have different areas of concern and emphasis. I'll have to ask Simon about it directly, but my guess is that even if he knows about the accuracy issue (I've not yet published my findings in graphical form), his concerns about velocity consistency are more pressing, all things considered. I also underbore when the occasion (or marker) calls for it, because of considerations that override the tiny accuracy benefits gained by overboring. Thanks again!
I was going to do a video showing my reasoning for overboring... what I wanted to focus on was how the industry tries to talk you into buying barrel kits over and over again while you really don't need them. I also find it interesting that the industry LATELY keeps saying "longer control bore... more accuracy!!" If longer control bore equals accuracy... then my 30 dollar CP 1 piece barrel must be the most accurate thing in the world.... its one solid 14 inch control bore!
The industry has floated around, in part because of ignorance in the old days, in part because of the need/desire to sell things, and in part because of the increasing popular push these days towards empirical data. Remember that there are a lot of engineers in this industry, and they want the best products, too. Testing is labor-intensive, and good testing can be very expensive as well. As for your CP barrel, remember that control bore is always measured by unported length, and usually requires a step in the bore at the porting to prevent velocity degradation if you are running a matched or under bore.
So i been over boring and I been liking it a lot more than matching it. Question is. How much should I over bore? I been using my stock Gtek barrel and have basically kicked my freak barrel kit to the side.
It's hard to say what the optimal overbore would be, based on a number of things. Personally, when I overbore, I like to run between .005 and .010 over, just to keep from wasting too much air. That said, rntlee did some testing that showed good results with massive overbores. Given how small paint is currently, and depending on your local supply, your stock barrel should give you an overbore situation just about all the time, so I'd just use that and not worry about it. To me, it's just one less thing to think about. Let me know if that helps (or not), and if you have any other questions. Thanks for weighing in!
Great video! Can you post the data collection that you used to make these conclusions? I've also wondered wondered if underboring causes consistent fps and efficiency because the ball deforms in the barrel to completely fill the bore, and then when it is mid flight that deformation causes inaccuracy.
Thank you! It's been three-plus years in the making in terms of the back research. And unfortunately during that time, some of the primary source links have gone dead, as have several secondary source links. The Paintball Times test, for instance, went dead sometime in the last three years. I cut and pasted it to a Word file originally, and have been working from that ever since. And many of the Punkworks results, linked in their videos, are dead also. I've gotten most of the pertinent links restored, but a lot of explanatory material was in the form of discussions on the Techpb forum, which is also unfortunately gone as well. So I've had to scrounge around over the last three years, and track people down trying to stitch things together. Thought I had put a request in here somewhere regarding information on lost links and the like, but it seems not. I'll fix that, and post the links that are still active, as well as places to go for additional info. As far as my compilation of the data, I've been trying to figure out a way to condense it so that it isn't just gibberish to the cold reader. There's just so much data out there that it can be overwhelming and I don't want viewers or readers to glaze over and die of boredom. The original intent was to get the whole series completed, then post everything in a dedicated thread in the forums. That way I could post whatever source material is still available, plus my data, and then unpack it by way of explanation. I'll post links in the description here, and can answer any specific questions if you like in the meantime. That will probably help to refine the final presentation, so by all means, feel free to ask away. As far as my methodology is concerned, I simply filtered out most of the testing noise (like which barrel is better than the others), and concentrated only on target consistency based on boring situation, kinds of paint used, target vectors and (where possible) velocity numbers. The hard truth is that there's no great mystery at the end of the tunnel, er, barrel. Paintballs simply aren't accurate, and barrels only make it worse to a greater or lesser degree, and there isn't much of anything we can do about it, and we don't like that, and so we often look for secret sauces or mojo, rather than accepting the reality and playing accordingly. To your second inquiry about underboring and its possible influences on both velocity and target consistency, In most cases of underboring, there is not a complete seal in the bore, but the deformation issue is a good point, and one I've made in the video following this one. I don't think it would be as significant as the spin induced by underboring, but it almost certainly can't be helpful. Well, a lengthy rant, but your inquiries were good. Thanks again, and let me know if this is helpful, or not.
What are your thoughts on "sorting" paint. Whether good or bad paint, if the main issue is inconsistency in paint as far as size and oblong shape, wiehgt etc - to what ever degree, couldn't you in theory sort the paint first by general roundness, say with a sensor of some sort to what ever margin you are comfortable with and then sort it by size of the paint - essentially just make various sheets with consistent holes and each sheet has a different bore size. Then you can weigh the balls individually. Obviously this would be more expensive and time consuming but for pro teams that expense may be worth it. I understand that perfect paint is "inaccurate," as far as accurate is unattainable, but wouldn't closer to perfect paint be MORE accurate than wildly inconsistent paint? Thanks for the great content!
Alex, great question. I would definitely advocate doing this (if you have the time and patience), and know of at least one person who does this with exceptional results. However, bear in mind that, as noted in my other videos, the best paint can ever be (including even Perfect Circle) is still very inaccurate. However, vs. what we get in standard even high quality bags of paint, this would definitely be something to look into. Some to think of it, sounds like good grounds for some additional testing....... :-) Thanks again for the great question, and welcome to the channel!
The paintball projectile itself has got to distort a lot, where I agree with you in that underbore would pinch the ball and when it leaves the barrel it'll be spun randomly causing inaccuracy, where overbore doesnt distort the ball as much.
This depends entirely on the size of the paint, but in general, unless you are shooting an autococker, you would want to be sure that all your paint rolls through. There's no need to be extremely wasteful of air with a ridiculous overbore. But I typically use .689 and call it a day, unless the paint is very small, in which case I'd go for the .685 just for a bit of extra efficiency. Hope that helps, and welcome to the channel!
If you get better accuracy from overbore but better consistency and velocity from underbore is paint to bore match not a nice inbetween? With that said I get some will end up a tiny underbore/overbore from paintball to paintball. Or was my freak inserts just a complete waste 🥲 I have a stock .690 barrel and my Paint is typically .682 so seemed a bit much maybe useful for a slight overbore . Newer player thanks
Ive done many tests with diff paint and bores. By far from what ive seen underboring is the least accurate. Bore match or slight overbore has worked well. I like a slight overbore but nothing crazy. Im not gonna shoot .682 paint thru a .696 barrel. .684 to .687 has worked well with .682 paint we have here lately.
We're flinging imperfect spheres at 200 miles per hour. These are made from materials that are affected by many factors. Once you understand all this, things start to make sense and for me personally overboring makes the most sense. Especially when quality control of paint is near nonexistent these days...
Could the relationship between underbore and loss of accuracy be attributed to average velocity overall going down? If so that would suggest that an underbore with an AVERAGE velocity equal to that of an overbore would be more consistent and possibly more accurate?
No, most the available evidence suggests it's ball spin. Ironically there is some data suggesting lower velocities may actually improve accuracy, possibly owing to reduced vortex shedding effects. Jury is definitely out on that one, so someone will need to do dedicated testing for that.
Whenever I under-bore I see a lot of balls veering so I always try to match or slightly over-bore. When I slightly over-bore I have a lot more consistency regarding my shots and little to no concern about barrel breaks. Over-boring works great for my Dfender (essential an Empire Axe in a mil-sim body), especially when ramping, but it is tricky to do with my Autocockers. I wish there was a way to employ a barrel detent with Autocockers like the old school Automags. I'd much rather slightly over-boar than match or under-bore. My experience has been mainly with Valken Graffiti which is my go-to paint. I don't like to shoot paint below this quality as they are more prone to breaking and not as accurate, generally.
Thanks for weighing in! Your experience reflects the data. For autocockers, you might try LAPCO's ball sizers, which are just short (1.5") underbore lengths that a standard barrel can be threaded into. I've used them with good results but the only issue (for me) is unscrewing them and trying to wrangle with the pneumatics. Otherwise, they work very well. The two potential issues with an automag-style detent is that (a) efficiency would likely go down by a wide margin and (b) junk from outside could easily get into the barrel. Lots of players run overbore with autocockers, with the caveat that you always either keep your finger on the trigger when moving (making the marker basically a temporary open bolt), or else keep the barrel up to ensure no rollouts. Thanks again!
The overbore/match bore/underbore data gets even deeper / slightly confusing when you throw into the equation devices on overbored barrels such as Palmer's Pursuit Shop "Wedge its", and "o-ring detent" barrels which prevent rollout in what would otherwise be overbored and thus roll out prone larger diameter barrels. Though before such came out to further muddy/deepen the equation, the old solution was: If you had to run or barrel down one would simply hold the trigger back on one's Autococker thus preventing the bolt from returning to the closed position. The shooter reliant on the Cooper T or wire detent to hold the ball just shy of the chamber.
Ive been running mid to high end paint with over bore and it's horrible, out of 3 barrels that are over bore. I finally got a freak kit and imagine it will help a lot. My grouping is about 3ft at 15yards with the over bore barrels and top tier paint. I tried some cheap paint and it actually was better in accuracy, it was tighter fit in the barrels where as the higher end paint would just fall out of the barrel
Three foot groupings at fifteen feet is indeed appalling. But it certainly isn't owing to running an overbore. Either the expensive paint was in bad shape, or some other factor is at work. The fact that you switched paint (even to a cheaper version) and got better results seems to suggest the paint is at least partially fault.
@@thatpaintballchannel179 it was 15 yards (45ft). The cheap paint was the worst out of shape and dimples. It had 2 dimples per ball. The higher end stuff I had on hand was graffiti and was measuring consistently at .684 and has performed great from other people's guns. But I guess with the freak kit I'll be able to experiment to fine tune it.
@@lemenscodyAh, my mistake on the distance issue. That sounded incredibly bad! :-) Still, even 15 yards is awfully short for that kind of spread. Well, by all means, do please post up your findings using the freak kit, though I'd recommend doing a side by side test with your other barrels for good comparison. Just out of curiosity, what kind of barrels are the overbores?
@@thatpaintballchannel179 I will. I plan on documenting it this weekend if the weather holds out. I forgot to specify I run mag fed on a Tmc (have ran the hopper, it made no difference). Stock barrel is .689, I tried the apex 2 which is .690 and the tippmann 16" sniper which is .690. Im not sure how the reviewers were getting great results because I've been bashing my head off the desk trying everything to get it to be somewhat accurate. Im not saying pinpoint like my ar10 but I want to be able to fire a 5 round burst at 50 yards and be able to hit a torso with 1 of those 5 shots or get very very close. I remember years ago I could do that with a pump gun. Out of the 3 barrels so far the apex 2 was the most consistent on vertical shot placement but would have wicked flyers left or right. The sniper barrel was all over the place and had a ton of left and right flyers, stock was like the sniper, all paint came from the same case in testing. I did notice some wide velocity ranges. All barrels about +/- 15 to 20fps deviation
alot pros just use a stock barrel a shocking number of them boreing your paint too close will cause the odd balls in the bag to fire weird compared to the majority... I mean how much are you actually playing I hear all sorta shit like "ive never broken a ball" & etc etc but people saying crap like that play like 1 time a month not 10 times like some of us things change when you really grind if you bore your paint too close to the ball size it will spin & it might only be 1 of 20 of your balls but that still is really irritating
what ive always wanted to see is the effect of paint viscosity on accuracy. we are shooting water balloons effectively that are not perfectly filled with an open bolt and even a closed bolt you are adding a sudden shock that will cause the fill to shift
Great points! However, this too has been tested to some extent. Viscosity doesn't seem to matter, and while the lack of fill can play a tiny role, it too isn't all that important. Even with completely solid paintballs (AGD made and tested these), accuracy is still very bad. In other words, no paint that you or I can get is ever going to be good, and even the best possible 'perfect' paint is still not good. So whether or not there is fluid sloshing around in the ball after it is launched, It's just the physics of the ball itself. Thanks for weighing in!
i come from a sac and long distance iron sights shooting (sharps rifle) so i get a bit anal about what i shoot for ammo (disclaimer most ballistics rules dont apply to paintball i know) there are so many minor factors with accuracy with paintball its a challenge to try and narrow it down e.g. and friend had horrible breaks and accuracy with his classic mag i changed the gummy bear like barrel o-rings and his troubles disappeared keep it up more testing and research always expands the knowledge
an aside another factor not looked at alot is how humidty and temp effect the gelatin shell and its....stickiness to the barrel and its deformation when shot
Almost forgot to mention: in the description of Episode 1 of this series, there's a link to a great intro article on paintball physics. It's older, and a lot more data has been added to the conversation, but it hits a lot of the major points, and goes a long way toward dispelling a lot of the hype and superstition surrounding paintball accuracy.
I'm saddened to say that the logic between these studies is closely related to face filter studies, where first level lab studies focused on filter efficacy for simulated aerosols (particulate matter) which showed they were effective at stopping most of the aerosols, and these studies are countered by empirical testing, control trials and meta analysis of these that conclude there was no difference in the % of people getting sickly, the face filters made no difference.
Well, a gel filled sphere isn’t exactly the easiest thing to get consistent ballistic performance out of. You might be able to eek out a little better results but there is no real control to base that off of. So it’s really a crap shoot
