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Airsoft-Ed

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Everything posted by Airsoft-Ed

  1. Ever since I started playing airsoft, and got involved in the whole game and science behind the guns and all this and that, to a deep enough level to understand it all, I have noticed joule creep. But it's only as of late that I've started to see it earn a name, and a gathering of people who actually seem to understand what it is. I first noticed it when I had an ICS L85 AEG, it was fitted with a 6.01mm tightbore barrel, 509mm long and fired .20s at about 360fps. I noticed that when I loaded heavier ammo, my fps wouldn't drop by as much as the conversion charts said it would. If you look at the equation used to work out muzzle energy, which involves the figures pertaining to ammo weight and speed, you'll notice that there's no mention of the length of the barrel, the bore width, or even the amount of pressure applied to the shot. Because it's just an equation, it isn't designed to be used in relation to airsoft guns, but it can be applied to them. As a result there are myriad variables it doesn't take into account, and this means that the conversion charts can be wildly inaccurate. The conversion charts are simply that. They convert the muzzle energy into different weight and fps amounts. It's like an on paper reference to using scales. Adding more of one thing here will balance out this thing here. The reality of it isn't so clear cut. Back when I first noticed it, the conversion charts said that loading .25s ought to reduce my fps by around 40, but I was seeing it drop by about 20. At the time I didn't realise that this would mean my muzzle energy was increasing, but it effectively meant that I was firing hot by around 20fps once I'd loaded the .25s. I was just counting my lucky stars that I was able to get away with having higher fps than the charts said I ought to be. However, now I've owned gas guns for a year, and I've seen it happen a lot more extremely, I've come to realise that the ignorance of not understanding it could lead to someone getting hurt someday, so my aim with this is to try and help bring attention to joule creep, and bring attention to... not how to counter it, but how to play with it safely. First, I'll try to better explain what it is and give an example of it. Joule creep is the name given to muzzle energy which increases when the gun is loaded with a heavier weight of ammo. The name, joule "creep" is given because the energy, measured in joules "creeps" up without it necessarily looking as though the muzzle energy has increased. It is common knowledge that adding heavier ammo reduces your fps, and many make the assumption that this drop in fps is a counter balancing effect which results in the muzzle energy remaining the same. You load .2s and chrono at 350, you load that same gun with .25s, you chrono at 315, muzzle energy remains the same. Right? Well, yes, sometimes. Joule creep is caused by guns sending more pressure down the barrel than the barrel can contain. Let's set up a hypothetical scenario: Gun A has a barrel which is long enough to contain 100% of the pressure that the mechanism sends down it in order to power the shot. So its cubic, volumetric capacity is large enough for all the pressure being sent down it to fit inside it. If you fire a .2g BB through gun A, all the pressure will be used on the .2, the .2 will leave the barrel and there'll be no excess air leaving the barrel once the BB's free of it. Adding heavier BBs to Gun A will see the conversion charts ringing true. Gun B has a barrel which can't contain all the pressure sent down it to fire the shot. It's only big enough to contain about 50% of what gets sent through it to fire the shot. So when loaded with a .2 it'll chrono at 350fps, but when the .2 is free of the barrel, it'll be followed out of the muzzle by 50% of wasted air. This is a gun that will see a lot of joule creep, because now when you add a heavier shot, due to it taking longer to accelerate out of the barrel, it is present in the barrel for longer, which means some of that "spare" 50% can be applied to the shot, and because more pressure is building up behind the shot, it is actually increasing the power of it. A .25 might use 60% of the air, a .30 75% a .46 95%... These are all just made up numbers to demonstrate the point, but can you see how a gun could gain power, that's muzzle energy, measured in joules. Kinetic, impact energy, that physically increases through the use of heavier ammo, all because the gun sends more power than required down the barrel. Joule creep is therefore significantly more prevalent in gas guns than AEGs. This is because AEGs use pistons and cylinders. Cylinders can only contain x amount of air, and they can be ported to reduce the amount of air they send down the barrel. Generally a factory AEG will be fitted with a barrel and cylinder combo that more or less match the barrel and cylinder's volumetric capacity, which will prevent joule creep from happening. Gas guns on the other hand, send significantly more gas down the barrel than required, simply by nature of the mechanism. It isn't something that can be reduced without it impacting the other performance characteristics of the gun. The longer and tighter a barrel is in gas gun, the worse the effects of joule creep will be. A longer barrel means there's more enclosed space for the gas to expand in, and the tighter the barrel means there's less space around the BB for the gas to escape. So I said I'd give some real world examples. A few months ago I set up my gas L85 to chrono at just under 370fps on .20s, because that's my regular site's limit. My L85 at the time was fitted with a 509mm long, by 6.01 wide tight bore barrel. Once set I changed to .28s which are what I generally run through it, and decided to chrono it again, just to gauge how much the fps dropped by. To my amazement, it didn't drop. I got more or less the same reading. In the ballpark of 370fps on .28s... I thought I might've got my ammo or my mags confused, so I double checked, but nope... According to conversion charts, a gun that chronos at 370fps on a .2 ought to drop to 312fps when loaded with .28s... But as I touched on above, this is because the equation assumes the same amount of pressure is being used to fire every weight of shot, but in gas guns, the heavier the shot, the more power gets applied to it. So My L85 therefore sends so much more pressure than it needs to down the barrel, that my fps remained the same because all the excess was making up for the drop caused by the weight increase. So if I'd gone to field this, I would have been firing hot by around 60fps, which is a joule increase of about .40. Today I thought I'd run the same test through my gas SCAR, so I chrono'd it on .20s, an average of 5 shots gave me a mean of 331fps. Loaded it up with .3s and did the same again, mean average of 290fps. According to conversion charts, 331fps on .20s ought to drop to 279fps, so that shows an increase in power of about 11fps from adding heavier ammo. Pretty significantly heavier too. My SCAR barrel is tiny too, I think it's 10" and it's not even a tight bore. That's a joule increase of only .08 or so, so it's pretty damn insignificant, but it proves the point that longer and tighter barrels, as per my L85 can take much greater advantage of it. Imagine if someone had a gas sniper, they set it up to fire at 500fps on .2s, it was fitted with a very long, tight as tight can be tightbore, and then they switched to .46s to play with... Ouch. So to be safe with your gas guns, ensure you look up the conversion charts, find the site's fps limits before you go, and work out what the limit will be on the weight you intend to use. Then when it comes to chrono, use the weight you intend to use, and set your fps to the limit you worked out. Conversion charts might not work with regard to the fps drop from adding weight being correct, but they are still correct in that x fps = x joules. So as long as you're setting your fps using the ammo weight you intend to use, you'll be safely within the limits. If you've read and understood everything I've just written out, or if you already knew about it, then help me spread the word. There are sites that ban the use of gas rifles because they don't understand the science behind the muzzle energy, or simply can't be bothered to deal with the need for people to chrono on the weight they say they're chrono-ing on. There are sites that force people to chrono using .2g BBs. This is ignorance, and it's potentially unsafe. Given any opportunity joule creep needs explaining in a way that people can understand and pass on, because the more people know, the less silly rules and regulations they'll be stopping us from using the guns that we love, for the hobby we enjoy.
  2. Anyone interested in how gas guns works? I've been making a lot of videos about them lately, including an extensive review, and a video explaining how gas pistols work. Links in comments.

    1. Show previous comments  4 more
    2. Colonel Kurtz

      Colonel Kurtz

      tried to watch it, but unfortunately it's too cold and my eyes only work properly in room temperature :) seriously tho good vids

    3. jay83
    4. jay83
  3. I need a Tippmann M4... Never been so impressed with an airsoft gun before. The kick is unparalleled. On auto it's legitimately impossible to hold your sights on the mark.

    1. Show previous comments  4 more
    2. Airsoft-Ed

      Airsoft-Ed

      when you fire it I think it's much better. More responsive and immediate, and it rattles the entire gun, not just the section with the moving parts in it.

    3. M_P

      M_P

      You get the buffer spring twang on a real one Ed ;)

      I think a way of reducing it though is to untwist the buffer spring a little, though I haven't personally tried it so can't comment on how well that works.

  4. What do you think of the SRS sights? I think they look awesome, but they seem to have just popped up out of no where lol, I feel like I don't know enough about them to justify buying one.
  5. A little I guess, but I wasn't ever going to play with the stock folded, it's just for transport and I thought the compactness was satisfying so I wanted to capture it lol.
  6. Been a while since I even visited this thread, let alone posted a photo. Just packing the kit for tomorrow and thought there was something immensely satisfying about the compactness of my SCAR, and I thought it looked pretty boss from this angle too. So here's an unbelievably high quality shot from my toaster:
  7. I know that in my first post I said it was too beautiful to give up on. Buuuuuutttt... I gave up on it. I'd suggest avoiding it like the plague to be totally honest. The feeding mechanism is just terrible, you might get the gun shooting perfectly but that will always be a weak link. The mags spray all their BBs out at the slightly tap as well, really not worth the money.
  8. Wow, the overall vote is for "no"? Seriously? It's a personal status update. It asks you to type, "What's on your mind" so if that happens to be, selling your shit, type it out. The space is for whatever you want it to be. If you're trying to sell something, why wouldn't you advertise it? When I'm selling my stuff I put it on 2 forums and at least 5 massive Facebook sales groups. The more places it is, the more likely and the faster it's going to sell. I'm struggling to think of anything wrong with doing it, apart from that it sends other updates off the page. But that's hardly the end of the world, and even regular, non-sales related updates do that. If people's updates were so important that having it pushed off the main page by a sales related update was annoying, or a problem, then why not make a topic out of it instead of an update? Or am I missing something?
  9. Not heard of that one before. Has the problem developed, or always been there? My first thought was that maybe you're using closed bolt magazines in an open bolt system. But I can see you have an L85 as well and I assume that's fine. I can't really think of anything tbh. Only other thought is that maybe the shell and the mag body itself have come apart and the gap between them is causing the mag to seat too high. But unless there's something between the shell and the mag itself stopping them from going together properly I can't see how that'd be the problem... It isn't really worth mentioning because it doesn't make sense for that to be the issue, but I thought I'd just mention anyway, 'cos you never know lol. The bolt knocking the mag out of the gun should be impossible though, so my bet would be that your mags are seating properly. Something to do with the mag catch maybe. Honestly clueless.
  10. Only if they were made of cardboard or something.
  11. Wouldn't need hop or anything! AAAAALLLLLLLLL OF THE RANGE.
  12. When I had the same AK, the top cover had a lot of play in it. Easily enough for putting a rail for optics on it to be effectively pointless. I went for a side mounted rail instead.
  13. HPA is exceptionally consistent, that's why people are moving over to it. It allows you to apply more air than could fit in a cylinder, and it allows it to be more precisely applied than it can be from a cylinder by a piston. Though gas is by its nature ridiculously inconsistent as it is temperature dependent, and using it lowers its temperature. The only reason gas rifles have anything like consistent shot placement is because they fire so much more gas down the barrel than they actually need to, that a shot has ample to use what it needs, so the shot weight creates it's own consistency in a way, by just making use of an effectively endless supply. If that makes sense? Of the volume of gas sent down the barrel, a .2 probably only uses about 20% of it, if that. The fact that there's still 80% helps with the consistency because how much gas gets applied to the shot depends more or less solely on its weight. Heavier shots will simply use a higher percentage of the gas supplied down the barrel. You'd probably need the barrel to be 2m long, or to use BBs weighing in excess of 1g before you got to the point where the gas supply fell short of the barrel volume. But yeah, back to the whole "cushion of air" thing. I just don't buy it. It's like heaven... It sounds nice, but frankly, it's too good to be true. So by the same token, I'll believe it when I see it, and not before. If a barrel is wider, the BB can more easily ricochet down it instead of flying straight, because there's more space for it to bounce around. If a barrel is narrower, then it'll get sent straighter. That just makes more sense to me, and based on the fact that tightbores are more accurate than not-tightbores, it just stands to reason that it's true. So how can a barrel that's wider than a standard one be more accurate? There is just no logic there that I can see at all.
  14. The principles at work aren't complicated, it's how they all work together and the sheer number of variables that make it an uncertain thing. Hop is just a brake that only acts on one side of the BB. More hop = more brake, so the bottom of the BB goes faster relative to the top, so you get more spin. Then obviously more spin causes shots to go up, less causes them to go down. That's the work of the Magnus effect. Heavier BBs can be spun faster without it causing them to climb upwards because of their weight, so they maintain their spin longer, as well as their velocity due to it taking more air resistance to slow them down, and so they reach out further, and carry their energy better. The one thing that I REALLY want to get my hands dirty and test properly, is whether or not widebores are actually better for accuracy at range. Because in my head, that entire concept makes absolutely no sense whatsoever.
  15. 150m sounds a little... bullshitty lol. I think 100m is about the absolute extent of airsoft range that can be useable tbh, 'cos once you lose sight of the shot to walk it onto the target, it could be doing anything, especially as the energy bleeds off. The longest range shot I've ever seen was 107 yards by a HPA bolt action sniper firing at 550fps and even then it couldn't be done consistently - there's a video of it: Here's a video my mate made using his P* DMR as well, I think he was hitting around 80m:
  16. Yeah, that's another factor. Whilst a gun using .2s and .25s might both be hitting the same muzzle energy at the muzzle, 25m down range the .2 has bled off most of what it had, whereas the .25 still has more. They'll also weirdly arrive at around the same time, because although the .2 sets off faster, it also slows down faster, whereas the heavier shot maintains a lower velocity for a longer period of time. So obviously the heavier you go with the weight, the bigger the energy transfer to the target, whether they're being dangerous with joule creep or not.
  17. If I had a chrono I'd make a video and demonstrate it. The best example I can give is with my gas L85. I once set it up for 370fps with .20s which is my site limit, and then I decided to chrono it again using .28s just to gauge the amount by which the fps would go down. I got the same reading... 370fps on .20s = 370fps on .28s. On .20s the joule output of 370fps is, according to this forum's app, 1.27J The app also says that if you chrono at 370fps on a .2, and then try with a .28, you ought to get 312.7fps BUT that's because the equation assumes the same amount of power will be applied to both shots, but it isn't. The heavier shot stays in the barrel for longer because it takes more energy to get it going, and because it's there for longer more energy gets applied. So because of this, and because gas rifles fire so much more gas than they need to down the barrel, I was effectively 67.3fps over the limit, and 370fps on .28s equates to 1.78J So I went from 1.27L to 1.78J with nothing but an ammo change. And there are sites that insist people chrono on a .2
  18. I now have 7 mates with Polarstars and when we're all running on the same team I don't feel that our chances of winning are any greater. I don't think they hurt more or cause more damage, it's just how they're set up. I think it's important to differentiate "HPA" and things like Polarstars and SMPs though, because HPA'd GBBRs are still a massive handicap over AEGs, unless they're using a casket mag or something. In fact you could even argue that HPA'd GBBRs are more of a handicap than standard ones because the reloads take longer due to the hose swap. You could still truthfully refer to them as "HPA" guns though. Polarstars and SMPs can be tuned to give the greatest performance possible from an airsoft gun for a lot less than it'd cost to do with an AEG, and more reliably, and in a more versatile system... But you need to know how. And a lot of people don't. A properly tuned Polarstar will rape the face off an upgraded AEG, hands down every time, they can't be beaten on consistency, it's just not possible. But the gun doesn't make the player. So long as site limits are met, I have no problem with them at all. As a GBBR user I feel that every gun I go up against has a significant advantage over me anyway, whether it be a standard AEG, an upgraded one, or a HPA P* or anything... Well, short of a sniper. So perhaps it's just my mindset because I choose to handicap myself on purpose. I think they probably should have set ROF limits though, because they're capable of 60+ rps and my site limit is 370... Many owies. Don't be a cock with the restrictions though, I'd say to set it at around 30. I'd argue that's getting close to being "too high" but it's what I'd aim for if I was building an AEG, and not for the auto ROF, but for the trigger response. Also since they're powered by compressed air, and the volume of it can be altered, and most people have no idea what any of that means... Joule creep becomes a factor. Especially when sites (dangerously) insist on chronoing everyone on a .2g bb. Guns should be chrono'd using the weight the player intends to use, because when guns have a barrel volume of less than what the gun fires down the barrel, adding heavier ammo increases the power. It doesn't stay level due to the fps drop acting as a counter balance. The fps drops by less than it should due to the way power is applied, and the joule output increases. It's especially dangerous in GBBRs, but also HPA rifles, spring snipers and to a lesser extent, long barrelled AEGs. So that might be why you feel like they hit harder, 'cos if they're set up with the poppet dwell on the longest setting and they hit the limit on .20s, when they add heavier weights to play with, they're actually going to be sending their muzzle energy, their joules, over the equivalent limit of .20s.
  19. Errrmmmm... That's a real one. Not relevant.
  20. Yeah if you want to use auto at all, or high caps, I'd get two or 3 if it's under 1500mah.
  21. Nah not been for months. Money troubles =[ Difficult needs to meet in a holster... You could probably get a fabric one you could adjust to fit whatever you want and have a little pouch for a spare mag... But personally all fabric holsters need to die in a fire lol. Rigid plastic holsters are where it's at. Fabric can flex, which means the weight of the pistol causes them to bounce around, which makes running very uncomfortable and can also cause the pistol to fly out. It can also make you lose your magazine, because the fabric can flex in a way that makes it hit the mag release button. They're just bad all around, especially leg drop ones. They take the whole "flap around causing discomfort" thing to a new level. Also, it sounds like a good thing to have your pistol mag fit into your holster, but when you come to needing it for a reload, it's honestly a massive pain in the cock. I'd rather have the mag in a pocket than on my holster, because my holster is on my right. I'm already holding my gun in my right hand. Reaching around to my right with my left hand is difficult, and reloading my pistol left handed just feels wrong and takes too long. Gun on the side of your strong hand. Mags on the opposite. Look on ebay for singular pistol mag pouches, I bet you could get one for less than a fiver. Airsoft is definitely a money pit, but if you can make things easier for yourself, and keep things cheap, then it's a win win, right? Lol. Anyway though, rigid holsters are a lot more solid... Duh haha. They hold the pistol more securely, they're 100% reliable, and they don't bounce around at all. Even the leg drop platforms are great, it feels like they've been sutured to your leg, just without the pain lol. I'm not a holster expert though... Finding one that allows a mounted tac light can be tricky. Rigid holsters are obviously designed to fit one shape and that one shape alone, so they can be fixed for only one specific type of light. They're very limiting. If you want to have a browse, then Safariland, or custom Kydex are probably your two best bets. But you're probably going to find they cost more than the pistol did. WE Glocks are also wider than their real steel counterparts, so if you want a WE Glock 17 holster you can either get the one made by WE - because that's designed for their overly fat Glocks. Or you can get one for a real steel Glock 21, which is the .45 ACP version and more or less the exact same dimensions as the WE G17, so bear that in mind when making your searches.
  22. Highly doubt you'll find any jobs where you can do mundane stuff such as peeling potatoes or collecting glasses etc. Minimum wage still applies right? No one in their right mind would pay anyone that young so much to do so little.
  23. Oh and yeah, The Stan do run mid week night games I think. Don't know how regular they are, and they might only be announced on the Facebook page, I'm not 100% sure. Sorry, forgot to mention it before.
  24. Airsoft is a hard thing to make a living out of at any age, let alone 14. I'd love to work in an airsoft shop, but obviously there has to be one near by, there has to be a vacancy, blah blah blah. There aren't really any other proper jobs to be had from airsoft. Site marshals have to be over 18, as do people in the shops for that matter, by the nature of over 18 sales being the predominant thing they do. But yeah, marshalling is only something you can do on weekends and weekends are when you want to have the time free to play! On the plus side, a lot of sites around here pay £50 a day and give you a free game day as and when you want. So marshalling actually acts as a pretty good way to fund airsoft, 'cos you can play for free, and spend the £50 on guns and shit. But yeah, 18+ only... Ignore me lol. You could do tech work for people, but I doubt you know enough to do that at this point, and honestly even though I'm more than competent, I don't do it even though I could because I don't have the financial backing to get me out of any issues if I accidentally screw up. So yeah... Paper round, as above. Got to be something like that you can find to do, go ask in the local newsagents or something. I used to deliver magazines from about 13 to around 19. 500 a month for just shy of £40.
  25. There's site membership, and there's UKARA membership. Site membership is specific to the site you're at, or a group of sites run by the same company. It entitles you to discounts, usually there's a lower rate to play at the site. So for example for non members it'd be £35 a day to play, but once you pay for membership which is valid for 1 year, you get a £5 or so knocked off the entry fee to make it £30. So if membership is £40 and you're planning on playing more than 8 times, then you'll make up the money you spent on membership, yeah? There could be other discounts too, it depends on the site. Sometimes sites host free membership days and things like that to make it a bit more enticing, as 8 times a year might be a lot for some people. I know most limit it to once a month, a few years ago I'd go 2 or 3 times a month at the same few sites so membership really made sense. But yeah, often sites will ask you to become a member before they send off your UKARA form, or stamp it for you. Because the UKARA number sort of ties you to their site, as you said the first 3 things in the number are a short code for the site name. For me it's SKI because I'm registered with Skirmish Airsoft. For you it might be TAC? UKARA is just a database so retailers know you're backed by an insured airsoft site. They give their say so to add you to the database by stamping your form 3 times in no less than 2 months. They scratch your back, so they want you to scratch theirs... Though given that you've done so by playing there makes charging you for UKARA seem a bit dickish to me, but that's just the way things are. Doesn't mean you can't go and play elsewhere, it just means that if you play somewhere 3 times, get your UKARA and then bog off, when you come to renewing it you'll have to play there 3 times again, or get it from a different place. 'Cos they won't have seen enough of you to account for the 3 games you need.
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