teflon don Posted November 10, 2009 Report Share Posted November 10, 2009 So a BB fired at 300fps will still be doing 300fps after 100m? Think again. It most likely won't even reach 100m. It'll be down to approx <90fps after just 30m (98ft) Check out the tables here... i never said that i said that if a bb travels 300fps avarage that it will drop 9.81 mters over 100meter Any (non-powered) projectile, fired horizontally over level ground, from any weapon, will hit the ground as quickly as one that's simply dropped from the same height as the gun it's fired from. Gravity works the same on an object whether it's travelling at mach 1, or it's just dropped from your hand. i know but a finned projectile will follow a predictable trajectory so you can lob your shots The reason you can't do that is because real bullets have a huge amount more power behind them, according to wiki a 5.56 4g round has 1,767 J, thats 1,767 times more than your average AEG has. EDIT : Plastic is softer than metal? Thats a bit of a vague statement isn't it? Some plastics are harder than some metals. i know im just saying that you can use rifling in airsoft as in rs we are allready talking about special types of bb why not a bb whit a softer outer layer so it will grab the rifling Link to post Share on other sites
teflon don Posted November 10, 2009 Report Share Posted November 10, 2009 You've just mentioned a bunch of stuff that "might" cause a hop-up to be inconsistent and then, with your next breath, make an arbitrary statement which you blindly accept as the truth without considering if the same issues will also apply to the alternative as well. so you are saying that a real bullet will spin slower or faster depending on dirt and oil no it won't More to the point, what happened to them? they went bankrupted what does that have to do with it Link to post Share on other sites
Rob15 Posted November 10, 2009 Report Share Posted November 10, 2009 i know im just saying that you can use rifling in airsoft as in rs we are allready talking about special types of bb why not a bb whit a softer outer layer so it will grab the rifling How would you polish the outer surface of the bb if it was much softer? The current polishing processes used for airsoft ammo work fine with the plastics used, I doubt they would with a softer surface. Simple test though, go get an air rifle barrel, some prometheus .177 pellets, remove the metal tip/core (block off the hole if there is one) and reduce the weight to as close as you can get with an airsoft bb then find a way to connect a 1j gearbox to the barrel (modified nozzle would be needed at least) and fire it. I'd be willing to bet that the force required to move the fairly soft (and they are a lot softer than bbs) prometheus .177 pellet case down a rifled barrel would be greater than the force a gearbox at around 1j can produce and the air would bleed out through part of the system. Link to post Share on other sites
08kecarv Posted November 10, 2009 Report Share Posted November 10, 2009 i never said that i said that if a bb travels 300fps avarage that it will drop 9.81 mters over 100meter So we play a sport where the BB stays at the same velocity regardless of how far away from the barrel it is and it never, ever, ever loses its velocity? i know but a finned projectile will follow a predictable trajectory so you can lob your shots So we'd essentially be playing airsoft football??? i know im just saying that you can use rifling in airsoft as in rs we are allready talking about special types of bb why not a bb whit a softer outer layer so it will grab the rifling The plastic of the BB wont expand like a bullet does to catch its rifling. There is no hot gasses or anything like that propelling the BB, making it expand and catch the grooves of the barrel. Unless you've got a 5.96mm barrel to hug the BB and make it spin, it won't do anything similar. Link to post Share on other sites
Chimpy Posted November 10, 2009 Report Share Posted November 10, 2009 I think it's time we raised the issue of whether a person can be suspended or banned simply for gross ignorance? This. That last page is quite painful on the old noggin. Link to post Share on other sites
teflon don Posted November 10, 2009 Report Share Posted November 10, 2009 How would you polish the outer surface of the bb if it was much softer? The current polishing processes used for airsoft ammo work fine with the plastics used, I doubt they would with a softer surface. i guess that finned projectiles don't need to be polished like a golf ball irregularities might make them more aerodynamic So we play a sport where the BB stays at the same velocity regardless of how far away from the barrel it is and it never, ever, ever loses its velocity? what ? So we'd essentially be playing airsoft football??? real snipers aim higher when they shoot at large distances and im talking about 5° at 300ft thats not that bad Link to post Share on other sites
Chimpy Posted November 10, 2009 Report Share Posted November 10, 2009 and im talking about 5° at 300ft thats not that bad Factoring in air resistance at STP what initial energy would need to be imparted onto a 0.2g spherical projectile with a 6mm cross-section to make it travel 300ft in one second? You also might think if you compared your mathematical model and reality that you have experienced as an airsofter you might realise that your model is a gross simplification. Link to post Share on other sites
elrey Posted November 10, 2009 Report Share Posted November 10, 2009 and im talking about 5° at 300ft thats not that bad You're talking about average velocity, not initial velocity, and you haven't calculated air resistance. Are we playing in a vacuum with airsoft guns that shoot 600 fps? Link to post Share on other sites
tome Posted November 10, 2009 Report Share Posted November 10, 2009 Teflon Don, before I put pen to paper and do my calculations please do share with us your maths and formulae. For a bb to travel 100 meters at an average of 300 fps what is the initial muzzle velocity required? What is the velocity as it passes the 100 meter mark? What is the angle of the trajectory from the horizontal at the 100 meter mark? Show us these formulae and your justification for why they are valid and maybe people will be less abrasive towards your ideas. Link to post Share on other sites
08kecarv Posted November 10, 2009 Report Share Posted November 10, 2009 You're talking about average velocity, not initial velocity, and you haven't calculated air resistance. Are we playing in a vacuum with airsoft guns that shoot 600 fps? So we play a sport where the BB stays at the same velocity regardless of how far away from the barrel it is and it never, ever, ever loses its velocity? Elrey basically said what I was trying to say what I wrote earlier Edit: Grammar. Link to post Share on other sites
teflon don Posted November 10, 2009 Report Share Posted November 10, 2009 You're talking about average velocity, not initial velocity, and you haven't calculated air resistance. you are wright i haven't taken air resistance into account i just kinda guessed that for a bb to fly 100meter in 1 would be possible For a bb to travel 100 meters at an average of 300 fps what is the initial muzzle velocity required? What is the velocity as it passes the 100 meter mark? there is no way to tell that because there is no way to calculate the ballistic coefficient of a bb that might be invented in the future You also might think if you compared your mathematical model and reality that you have experienced as an airsofter you might realise that your model is a gross simplification. exactly with that simplification i can show that you don't need a hop up you can just aim 5° higher @100meter im still convinced that you don't need a hop up as long as the ballistic of the projectile is consistent you can get alot of range with a regular airsoft gun without a hop up by aiming higher now if you have a projectile that keeps its speed longer and that follow that same trajectory 100% of the time youll have better or at least the same effective range the only way we will know for sure is if a company develops and test a whole range of different projectiles there is a reason why al the airplane a car company's use wind tunnels test because you cant predict aerodynamics i say that its possible and i couldn't care less what you guys think there have been a number of different companies who tried it do you actually thing that they would risk their money and repution on something that is doomed to fail Link to post Share on other sites
elrey Posted November 10, 2009 Report Share Posted November 10, 2009 you are wright i haven't taken air resistance into account i just kinda guessed that for a bb to fly 100meter in 1 would be possible If anyone's Wright, it's definitely not you. You'd never have gotten an airplane off the ground with those kinds of calculations. Link to post Share on other sites
Docv400 Posted November 10, 2009 Report Share Posted November 10, 2009 Lead is softer than the plastic used for BBs. Try marking lead with your fingernail, then try it on a BB. Rifling will not work with plastic projectiles at the sort of power Airsoft guns have. It would take way more energy to force the plastic projectile down the barrel than any Airsoft gun can provide. I never said that. I said that if a bb travels 300fps avarage that it will drop 9.81meters over 100meters You can't apply a theoretical model to something like this, nor can you apply average speeds to it. If you fire a BB at 300fps, then the average speed (from firing, to it hitting the deck) will be much less than 300. You also have to accept what actually happens, and that is that the BB slows down enormously over that sort of distance. As I said, I doubt a BB would even reach out to 100m, even if you fired it at the optimum angle for maximum distance. Link to post Share on other sites
Chimpy Posted November 10, 2009 Report Share Posted November 10, 2009 you are wright i haven't taken air resistance into account i just kinda guessed that for a bb to fly 100meter in 1 would be possible Then you are an idiot. there is no way to tell that because there is no way to calculate the ballistic coefficient of a bb that might be invented in the future. How about with a BB that exists now? exactly with that simplification i can show that you don't need a hop up you can just aim 5° higher @100meter Again you are an idiot. What I was saying is that your model is too simple. It ignores key factors that need to be taken into account in order to produce a simulation close to reality. you can get alot of range with a regular airsoft gun without a hop up by aiming higher now if you have a projectile that keeps its speed longer and that follow that same trajectory 100% of the time youll have better or at least the same effective range And if I'm careful with my gene splicing I can make a Unicorn out of a horse and a rhino. This is not to say there aren't further technological improvements that could be made. It's just your rationale is shonky. Link to post Share on other sites
Rob15 Posted November 10, 2009 Report Share Posted November 10, 2009 with that simplification i can show that you don't need a hop up you can just aim 5° higher @100meter Are you sure about that? Take the hopup out of a regular AEG and you'll be struggling to get 30meters range even if you lob the shot, let alone 100! Without hopup gravity will and does pull bbs down and causes them to drop like stones after a very short range regardless of how much higher you fire, I suspect that actually lobbing shots would be counter-productive in that case as the energy would be getting used to fire the bb upwards rather than across to the target. Link to post Share on other sites
08kecarv Posted November 10, 2009 Report Share Posted November 10, 2009 Teflon you're still not taking resistance into consideration; we wouldn't need a hop up if there was no such thing as air resistance, but we play on earth where there is. Therefore, all your previous statements are made invalid. Link to post Share on other sites
Chimpy Posted November 10, 2009 Report Share Posted November 10, 2009 teflon don - I was a bit mean calling you an idiot. But you need to realise that the criticisms bought up here by multiple people are very valid and are the reason why your conclusions are flawed. Link to post Share on other sites
shibisueka Posted November 10, 2009 Report Share Posted November 10, 2009 I'd have to agree with the opposition here, teflon. Sure, if it was done particularly well, it might be useful to snipers. But that's about it. There's no real way to make it cheap enough to consider everyone switching. Link to post Share on other sites
Stealthbomber Posted November 11, 2009 Report Share Posted November 11, 2009 FWIW, I really don't think the practical elements would be that big of a deal. Particularly with the way GBBR mags are made these days, it'd be pretty easy to replace that front part with a BB-tube shaped to fit a shaped projectile. Beyond that, you built yourself a hop-up that has an oblong feed-tube and then make sure your nozzle is long enough to push the elongated BB into the breech. Again, this shouldn't be a problem on a GBBR where you've got a bolt moving 3" although building a sector gear/tappet plate that can move a nozzle far enough might be hard. This theoretical discussion is really going nowhere. Quite simply, if anybody wants to give this a try they need to get themselves a batch of finned/skirted BBs made up (I'm sure Rob_15 could help you with this), shove em into an airsoft gun of some sort (I'd recommend a GBB pistol for ease) one at a time and shoot em with the hop-up dialled right back. When you've done that come back and let us know how it goes. I would, however, suggest that the person who does this presents their findings with a LOT of video and photographic evidence. A couple of graphs isn't really gonna convince anybody. Link to post Share on other sites
Danke Posted November 11, 2009 Report Share Posted November 11, 2009 A guy over here made these and they grouped worse than a variety of other BBs out of a Maruzen APS2 with no hop-up. Range was 90 feet. There were no keyholes and the projectiles didn't break up. They were just all over the map. Link to post Share on other sites
frogfish Posted November 11, 2009 Report Share Posted November 11, 2009 they went bankrupted what does that have to do with it Ermm no, they ended up having legal issues because the M40 could be modified fire a single .22 round before being permenantly damaged, enough by the Japanese to get Asahi in hot water. So if the Rap4 airfin has been around for so long, I'm counting at least two years now, why hasn't the RAP4 system become the industry standard? Because their mech is ######, no not just that, but because with the way airsoft guns work, they don't fly like a football, even with rifling they tumble. People bring this up just about every other month between the sites that I'm on and simply put, people have tried everything else, and the only way to make it work is to develop a whole new system, not simply turn the hop-up off and rifle the barrel. With the way many players play who wants to sit down and load 300 individual rounds for a day at the field? I'd much rather suffer with a 200ft AEG. If you are really desperate for range there are other systems that can hit 300ft flat at reasonable speeds but this is not the place for that discussion, as there are many people who doubt it. Link to post Share on other sites
derf Posted November 11, 2009 Author Report Share Posted November 11, 2009 I've been emailing RAP4 for information regarding Airfin. It's turning out to be quite comical. I have the urge to give Jasper a right good flippin' thump to the face. Most of the times, companies are willing to fill you in with all kinds of information and claims when you ask for a product because essentially they want to sell you it. Me: Hi RAP4, What are the benefits of Airfin? Thanks. Jasper Batuampo (RAP4): Airfin helps you shoot more accurate and helps you shoot farther. Jasper Batuampo. Me: Hello Jasper, Compared to what, and approximately how much? Thanks. Jasper: when comparing to standard bb, the airfin stabilize the ball in flight by making it aero dynamic. When it comes to distance, it very hard to say lots of factors to calculate. Jasper Batuampo. Me: Hi Jasper, Surely there's some data somewhere or at least some kind of USP to this product? Thanks. Link to post Share on other sites
frogfish Posted November 11, 2009 Report Share Posted November 11, 2009 He's beating around the bush...you'll find they can't give you any info on if it's better, because in a RAP4 it does help you get like an extra 20ft, but whats 20ft when your only shooting 75 in the first place. RAP designed an airsoft gun around the way paintballers play, close quarters paint swaps, that dosen't happen to much in airsoft. Just remember that with the airfin you also need to buy the spacers so you can shoot them....so not only do you have to sit and load 300-1000rds but you also have to load them into little shells so the rifle can use them. tack on another 3 hours to the game day prep.... I'd hate to have to reload on the field... Link to post Share on other sites
Stealthbomber Posted November 11, 2009 Report Share Posted November 11, 2009 We should probably stop paying so much attention to RAP. Their products always have been under-engineered cr*p so I really have no idea why we're putting so much faith in their innovative skills over this. Far more likely that they invented the airfin BBs as a way to extend the range of their guns without having to significantly rework the internals. ....which they HAVE now done. You can buy a chamber for the RAP M4 which converts it to shoot BBs from airsoft mags and has... a hop-up! Why would they do this if they have so much faith in their Airfin BBs? Anyway, this is a company that spent months (in fact, years) developing rubber BBs and then acted shocked when it turned out they couldn't be made to travel down the barrel smoothly. RAP are not a company to be trusted. Link to post Share on other sites
greg Posted November 11, 2009 Report Share Posted November 11, 2009 For airsoft, we don't have any such practice OR data.[/u] Merely rumour (correct me if wrong). It's not a roumer. Turn your hop off, find out for yourself. Do a search as this has recently been covered in the sniper heaven section. Non-spherical bbs can not be hopped. This means that ballistic trajectory, caused by gravity, effects any non-hopped projectile. Folk have to be able to 'feel' their hits. Extending range & accuracy, beyond the point at which a hit can be felt, is pointless. Arcing long range shots in, by aiming high, may extend range, but if the recipient thinks it's a rain drop or doesn't feel it at all, what is the point Have you ever played airsoft? Greg. Link to post Share on other sites
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