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Firebeard

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Posts posted by Firebeard

  1. About the next version... Ron has been sick, and I haven't been expecting it to make much progress. It's done.

    Build 7 is, from a brief trial run, operating as it should be. A few added tweaks are in, such as Grenades now work in the quick-grenade slots again, and explode at the end of the turn (new feature the Devs added, which is being made full use of).

    Go to the mod page I'm linking to now or use the link in the OP: http://xeno-mods.com/mod/154/quasi-realism-alpha-for-version-19-build-7

    Let us know what you find while testing.

    Aside from the exciting news of a playable version, we would like some help in a real-life test, as Ron describes.

    "This is my problem with forum discussion. No definitions. No frame of reference.

    It's heavy, compared to an origami display. It's light, compared to a train bridge. It's controllable, compared to the weather. It's less controllable than a herd of cats. "Accurate" for a full-auto weapon pretty much equals "totally random" for a bolt-action rifle. A statement can be "correct", and still useless.

    If these guys have access to the weapons in question, how about some tests? Let's get some numbers to work with.

    Test procedure:

    Needs one shooter and one person on a stopwatch. Several targets - humanoid, or round, or whatever, as long as it's constant through the tests (and roughly the size of something you might want to shoot ... not a billboard) - set up on a safe range preferrably far away from other people or much of anything else. (This could get a little wild, as far as shooting range safety goes... Not exactly "unsafe", but not exactly procedure either.) Start with about 25 paces on the range to targets, retest at 50 if time and ammo allow.

    Need a basic rifle - modern assault rifle preferred, but any good rifle will do for the single-target test, and any semi-auto rifle will work for the multi-target variant. And the weapon(s) to be tested for comparison - in this case, a light or medium belt-feed infantry machinegun. Do note the make and model of all weapons involved, for reference.

    Now, set up a basic snap-shot drill. Stand facing 90 degrees to the targets, with them to your preferred weapon side (i.e. your left, for right-handed shooters). (If you wish to repeat the test for your non-favored side or directly behind, later, repeat and note the difference.) The stopwatch person says go and starts the time, representing the point at which you identify a target and decide to fire (instead of diving for cover, or any of the other things you might want to do). Bring the rifle to shoulder and try to fire as quickly as is reasonable (i.e. a "snap shot"). Repeat until a statistical pattern on the times is apparent. Record the times, and note the percentage of rounds that were on paper.

    If time allows, repeat using slightly more time to aim, to represent the more aimed fire in the game. Note change in time and accuracy.

    Then repeat the test with the machinegun, firing standing, from the hip or shoulder (preferably testing each), as simulated in the game engine ... note specifics of firing position in the results. Run tests with bursts of varying lengths, to compare. This should give a pretty good picture of the time required to get a heavy weapon situated on a target, and the relationship between rounds fired and accuracy.

    If opportunity exists, repeat all tests with three targets, situated at slightly offset ranges and at least 15 feet apart laterally. One round per target with rifles, bursts of varying lengths with full-auto weapons. This will be easier for your stopwatch guy, too ... rifle snap shots are fast enough that timing one of them can be tricky. (Don't bother testing walking full-auto fire across all targets in a sweep - the game won't let us simulate that at this time, either.)

    Another variant, if you have the time and resources, is to repeat this with a handgun. Try both with the weapon in-hand, and having to draw the weapon to fire.

    If you have a video-equipped camera, it might be easier to check the times if played back one frame at a time. 30 frames a second is a little faster than normal human response on a stopwatch button, so that data should be more precise. With that, a light or buzzer to singal when to fire could replace the second person, if you're doing this alone.

    Even if you're not collecting data for a computer game, it's a fun test to run, just to find out what you can really do with the weapons in question. And a table of those numbers would give everyone a point of reference - time and accuracy in concrete data (seconds, and bullet holes in paper), not vague generalities open to interpretation. If several people could do this experiment, preferably with more than one type of weapon, it would solve the issue completely ... we would know exactly how long it takes to fire an MG from the hip, and exactly what is the preferred firing method (in terms of burst length, and benefit of various lengths of time to aim).

    If you do try this, do be careful. Fully automatic weapons fired hurredly from unstable positions is generally a formula for an accident, even among highly trained shooters. And as funny as it can be to see a news headline like "firearms instructor accidentally shoots self in class", I really don't want anybody getting hurt.

    -------------

    Until I have those numbers, I'm going to guess... I don't know of any military or law-enforcement studies done on the benefits and drawbacks of using a belt-fed weapon from the hip, so actual data is sketchy. If you do get a chance to test this, please note the results precisely ... don't average them for me, or some such. I may be able to pull statistical trends out of the raw data that you might have missed.

    This test does not include what military calls "suppression fire" (as in "we were just shooting to scare them") and everyone else calls "panic fire" ("you were just shooting because you were in danger, and it seemed like a better idea than just sitting down and crying"). (For the record, it is more effective than crying, but only marginally.) While the game engine does include suppression mechanics, I'm not really sure we could simulate this, even if everybody agreed it was a good idea.

    This should find out who really wants to help, and who just likes to hear themselves talk. If they really want this mod to go forward, they can contribute some time and some ammunition."

    Firebeard: I would be quite interested in seeing the definitive manual you mention.

    Normally, I'd be all for this, but given the preponderance of evidence that already exists(there's been studies since before WWI), deaaling with accuracy, walking fire, etc, like hell am I spending the several hundred dollars it would cost to do this test(and given that these tests don't actually demonstrate what we're trying to prove here), for the same conclusions that have already been proven. They don't just randomly decide on doctrine, they've done studies on MG employment in the US following the first world war, world war two, korea and vietnam. What you describe, hipfiring an MG, is called "walking fire", and has been a Thing since man portable automatic weapons have been(in fact, several squad automatic weapons were designed with this in mind). We /have/ figures for what you want. Comparing the accuracy of hip fired rifles, to that of hip fired MGs, isn't even remotely accurate, nor would comparing rate of fire, or recoil chracteristics. Of course, even disregarding the above, your proposed tests would geenerally violate nearly all ranges' rules, excepting some 270deg ranges for 3 gun matches.

    As for how long it takes to fire an MG from the hip for any given burst, look up the rounds per minute of the MG, divi8de by 60, and then multiply that figure by how many seonds our little support gunner guys are going to fire(dotrinally anywhere from 3-5 seonds, I'm going to defer to the two guys here with prior infantry background as to how long the burst should be). For an M240B(the infantry variant), that burst is going to be anywhere from 33 rounds(the low speed 650rpm setting, for three seconds) to 63(750rpm setting, for 5 seconds). For an M240G, you're looking at a low of 33 rounds(650rpm, 3 seconds), and a high of 80 rounds(950rpm setting, 5 seconds). Potential rate reductions due to fouling excluded, since they're fairly minor.

    I don't know how to upload the pdfs. Could you point me to a good place to, or would you prefer I email them to you. It's several volumes(some of which are broken up into parts for size).

  2. Ron is feeling a bit better, now. He still has a lot of code to sift through before he can even start fixing the mod around the new updates... so we're still a little ways off from build 7.

    He also felt well enough to reply.

    "This is why I was originally only going to give this mod to a few people, and not release it public. Any time you try anything like this, you get flak from two sides. One side understands the game engine but not the realism, and they're like "Can you make your agents do jump kicks?" The other group has some background in realism, but hasn't worked with the game engine (at least not nearly enough), and they're going on about how something is really used, and not taking into account that the game simply can't or doesn't simulate that. And neither group understands the concept of "This is Alpha, we're still working out the details."

    I don't really disagree with what those guys are saying ... but there's an issue. They're talking about setting up an MG and using it like it was intended to be used. Two man crew, a loader making sure the ammo feeds and changing barrels when they get hot, firing from bipod or tripod in a prone or seated position. Problem is, that's not what we have to work with....

    The game engine models the little X-COM dudes running around firing a belt-fed weapon from the hip, kind-of pointing it in a general direction rather than aiming. This, realistically, tends to result in bullets striking more ducks and geese than the intended targets, more so if you fire more than a short burst. Also, if you just lean on the trigger, you can't really change out the barrel when it gets hot ... so you can completely melt down most guns, at least enough to screw up the ammo feed in some significant way. Playing like you think you're "Rambo" is an extremely inefficient use of a squad automatic weapon.

    So they're not lying. They have seen these weapons used ... specifically, they have seen them used in a reasonable way by trained military. But I just don't have the ability to modify the current game code to really show this. I can model what seems to be happening, or I can model what you might want to be happening ... and either one is going to fail to simulate the other.

    If somebody wants to talk to the developers about getting prone firing positions and setting up crew-served weapons ... we might be able to do something with that. Until then .... well, I'm doing what I can with the tools I have."

    "Almost all infantry light/medium machineguns are, in a word, too darn light for what they are.

    Even my granddad told stories about the air-cooled Browning M1919A1 ... even it was too light. It walked like crazy, unless you went to extreme measures to nail it down to something, and it heated like crazy."

    See, I /have/ shot a 1919(A4 and A6 variants), including an A6 from the hip(aided by a sling, because it weighs just under forty pounds). None of them were "too light". In fact, they rank way up there as "so heavy they're nearly unworkable for what they are". Other countries have fifty cal MGs that weigh less.

    I've actually shot a pretty wide range of MGs(1919A4, 1919A6, RPD, M60(mod unknown), M53(yugoslav MG42 clone)), the A6 and 60 from standing as well. They're a real treat to shoot. Echo has time on the 240, 249 and probably others. I've also burned through plenty of ammo on SAW type weapons(RPK), SMGs and a range of other guns. I've accumulated a lot of trigger time on older weapons, and the shop I worked for was an FFL07/02SOT shop. We didn't just play with them, we /built/ them.

    As for heating, the testing that the 1917 and 1919 underwent prior to adoption involved some positively brutal continuous fire. Prior to WWII, ALL MG's adopted by the US Army were torture testede to rediculous standards, up to and including continuous fire of over 200,000 rounds for the 1919(and more, although I cannot recall how much, for the 1917 and 1891). Yes, they get hot to the touch well before that. But nowhere NEAR hot enough to damage the firearm. You start running into throat erosion after a few belts of continuous fire, but even on guns without quick change barrels(such as the 1919, which changing barrels on is a complete and total pain in the ass), throat erosion is not an issue for a bullet hose like we're modeling here.

    I /have/ run out a couple belts in one sitting, at one point. It as a friend of mine's final send off(he'd died of a heart attack, and was a huge MG collector, so we did one massive magdump at the range as part of his wake). Four hundred rounds continuous, from his M60. Through one barrel. Unlike in video games, they long since remain functional despite getting hot. AND, even if they do start having heating issues, the part that wears is NOT the "feed mechanism". The feed tray and tgopcover are far enough away from the heat that pretty much everything else on the gun will be fucked up first. What you can expect to see is excessive throat erosion(which will, eventually, trash the barrel for accurate fire purposes), followed by eventual deformation of the barrel. To get to "barrel deformation and loss of correct headspace" on an MG requires heating the barrel to the point of plastic deformation, so you're getting up into the hundreds of thousands of rounds continuous fire. Some MGs may experience malfunctions long before this, due to fouling, or heat expansion affecting tight tolerances, but those still run into the thousands of rounds of automatic fire. Are you laying accurate fire, no. Are you laying fire, absolutely.

    The most likely malfunction is a jam due to belt malfunction, if you have the belt hanging loose rather than in a box like everybody in the world uses for carrying belted ammunition.

    For accurate, real information, instead of going off of he word of random people(self included), I would STRONGLY recommend you find a copy of George Chinn's "The Machine Gun". I might be able to upload my pdf copies somewhere for you to use. They are The Bible of MG development and use, from a mechanical perspective, and deals specifically with automatic weapons throughout history. It has diagrams, figures, formulas and everythging you need to know about automatic weapons.

  3. UPDATE: Ron agrees about the machine gun.

    "I lowered the AP cost on the MG by a bit, because I thought so too ....

    Note that the weapon shown - the FN-MAG (NATO designation M240) - is a kind of light gun for its caliber. It doesn't handle recoil well, and tends to overheat and cook off rounds if you fire longer bursts. So some compromise seemed to be in order, to prevent players from being able to burn the entire 50-round belt without pause."

    To be perfectly frank, Ron doesn't know what he's talking about.

    In the first case, the M240 fires from the open bolt. Ammunition doesn't cook off in the gun, period. You'd literally melt the receiver(also impossible, you'd have catestrophic failure of the locking lugs, and the barrel before then) before you got the round sitting in the feed tray to heat up enough to cook off. So yeah, not only is this not going to happen, it's evidence of his ignorance. Anybody who's operated one, or fondled one, or played with /any/ LMG excepting some of the wierd russian squad automatic weapons fires from the open bolt. For thsi reason.

    Even amongst the very few LMGs that /do/ fire from the closed bolt(and even lumping in the very light russian SAWs like the RPK series), you can /still/ fire a LOT of ammo before a cookoff. On the order of thousands of rounds. People have set the handguards(wood) or melted them(polymer) of those weapons on /fire/ before causing a cookoff.

    Ammunition cookofffs are effectively a nonissue amongst ANY weapon, unless you're doing WWI style masses of constant LMG fire(I recall one battle in which three MGs went through a combined total of just over a million rounds, in a day). The testing that any weapon from the modern era undergoes before acceptance and issue tends to far exceed combat stresses, and this is especially the case in sustaned fire and mean-round-until-failure tests.

    Two, as Echo says, the M240 is the US designation, and it is one of the /heaviest/ weapons in it's class, among modern designs anyway(WWII era and earlier designs are frequently heavier), although even some much older designs(MG 34, MG 42, BAR, DP28, DPM, RP28, BREN, pretty much everything but the Browning M1919 series) weighed less than the 240 does. Among beltfeds, it is the heaviest currently issued GPMG. Even including the wierd russian designs.

    So yeah, I would disregard most of Ron's input, and I would stick to realism as much as possible.

  4. I might just change the story so the Xenonauts can only hire the soldiers that failed their entrance exams everywhere else. It'd stop all the complaints about them being such bad shots.

    Also, I will be looking at Pinetrees' mod. I intended to add a lot more nations to the soldier lists but then got caught up in some other stuff, so duplicating his work seems a bit silly.

    >"Why would you trust the world to these people when the UNSC just told you to get the best you can?"

    >"Because they were cheaper. Hey, wanna check out the new Gulfstream V I just bought?"

  5. I'd like to second the notion of flamethrowers and grenade launchers being implemented.

    Flamethrowers, ideally, with a realistic(or, well, adjusted for balance and gameplay) range, rather than the hollywood 20ft one.

    Perhaps to balance GLs and rocket launchers, it might make sense to have the GL have a reduced power or radius from the hand grenade(handwave the GL grenade as being HE rather than frag maybe?), but longer range, while having shorter range than the heavier/slower rocket launcher?

  6. Balllistic test speak agaisnt you when it comes to range penetration and damage but you state it yourself later so i don t get your initial statement.

    Muzzle rise is controlable as long you dont burn the full clip in one press, just adapt.

    The RPK is more capable at defeating armor than the saw AKA Minimi AKA M249.

    Agree on the optics but unless damaged would you remove them on the field ?

    Agree on recoil, but auto and only 3rb is so screwed in the game they are usefull only in Point Blank. I hope that will change.

    Since when AK74 have side magazine or RPK, i m lost here ?

    Strange, M14 is back to the specops, modernized of course, its a 7,62, sure its NATO. But the the ANP90 called AK100 is back with 7,62...So its not SO dead, it has it uses it seems.

    And i already heard a lot of USA soldiers, inclusive ballistic tester saying shit about the 5,56 compared to some aspect of the 7,62... So who do i believe ? Nice propaganda by the way.

    All is simply a trade off question brought for in by the Nam, number of round versus effectiveness. Basicly the 7,62 is more damageing and has greater stoping power while the 5,56 has more penetration and in know to go trought the body leaving the combatant able for some time, while this rarely happens with 7,62.

    On the counterpart 5,56 travel further and has better penetration. Since penetration doesn t exist in the game.

    M14 had a 90% killing rate before being replaced. But in patrols soldiers tended to get out of ammo due to carrying weight limitations. This tended to be a problem especially when CP streched much farther than the counterparts.

    And comparing modern cartridge agaisnt 30 years old one is that smart, ballistic and ammo have evolved a long way.

    But all this is useless what i want is a bit more options. Maybe this seems useless as you develop other weaponry very early in the game, assuming your lucky enought to down enought UFO to make enought money, but options tend to bring something called replayability... which tend to be good for games.

    As for my ideas i already found other people post that tag along those. Plausible cenario + more options. But hey modders are for such, right ? Why bother the developers with such things....

    Let people have more of the same if they want.

    Some people like modern cars, some people prefer vintage ones.

    You speak an awful lot of the same tired, overly repeated myths.

    In ballistic testing, 7.62x39 does considerably less in terms of permanent cavity damage than either the 5.45 or the 5.56, wich 5.56 being consideraboly more effective due to fragmentation effects(compared to the tumble effects of the 5.45, which creates a considerably larger temporary cavity, which is fairly irrelevant in terms of immediate effectiveness, even though it may render a much larger area of dead tissue in the long run).

    5.45 out of an RPK74 has less armor penetrative capacity than a 249 firing 5.56. 7.62x39 penetrates a thicker layer of steel, yes, but atthe cost of significantly less effective terminal ballistics, significantly reduced range(7.62x39 has an effective range of 350yds roughly, compared to the 500-600 for either of the other two rounds). The RPK is also considerably less accurate as a platform, due to the shoddy machining tolerances it is manufactured towards, and as much as loose tolerances is spun as a design feature, when it gets so bad that you have to number and sort your parts based on how in-spec they are(AK platform weapons parts all have small numbers on them, indicating whether they are slightly undersize, in spec, slightly oversize or very oversize), because otherwise you can't put them together and have them work, it's not a feature, it's shitty quality control.

    The AN-40 and AK-100 in 7.62x39 are offered for export use, and are not used internally. Or, for that matter, by ANY military force in the world. At all. Ever.

    The 7.62x51 was not brought up, but there's a reason NO nation uses it anymore for a main line rifle. It suffers from excessive recoil, while being entirely more weight than is needed. The M14 was not a wonder rifle, it was a rifle that was dropped from main line infantry use very rapidly on account of it being underperforming compared to either of it's contemporaries(the G3 and FAL platforms). It did not have a "90% killing rate". I can't think of any round that fits into an infantry rifle with that kind of performance, or even close to it.

    Have you ever shot an AK or AR platform weapon on auto? If so, you would know immediately that your claim about controllability. I've shot both(several variants of both, actually). An AK on auto groups absolutely terribly, with hitting a man size target with all rounds of a burst at any reasonable difference being nigh impossible. While an AR pattern weapon on auto is extremely controllable, albeit still less acurate than it would be on semi, keeping all shots in a burst in a head size target at 100yds on auto is entirely doable.

    It is worth noting that even Russian and Chinese special forces uunits operate M4 platform weapons(either purchased, license-built or clones). Literally every special operations force in the world that has the money(meaning all the competent ones, plus the Russians and Chinese) run M4 platform weapons now. There is literally zero reason for any country to be using a substandard weapons system except for cost reasons, and absolutely no reason at all for an elite paramilitary unit(like we're discussing) to run such a substandard weapon.

  7. Diference of ammo. Nice for for an army irrelevent for for Specops. And why american weaponry and not russian anyway. Ak74 has better characteristic for the ranges we use compared to western side, same for RPK agaisnt the model pictured, western snipers were more accurate on western side. Again are we a multilateral org or fenced stringed toy ?

    Wouldn t you prefer a more damaging ammo on some situation that travel less, than a lighter less damaging ammo ?

    Why can t we players choose ?

    All this can be done and is done by modders...and could be incorporated into the game before release.

    I'll go a little further than Echo. Russian weapons offer literally zero advantages over western weapons(which is why you see even some Chinese units operating license-made M4s now). The AK platform is heavy, the stock configuration(specifically the amount of drop it has) makes effective automatic fire with it much more difficult due to increased muzzle rise, the RPK has those problems and a low capacity for a SAW, none of them can readily mount optics in a way that will retain zero when removed and reinstalled(AK sidemounts are possibly the only thing worse than the G3's claw mount, and that's really saying something). Reliability is a nonissue(both Western and Warsaw Pact weapons tend to be considerably more reliable than tthe internet would have you believe), although the mechanissm that supposedly makes the AK "more reliable" in fact results in increased felt recoil. In addition, the AK platform weapons have extremely clunky manual of arms, making anything you haave to do to operate the weapon that much slower. Paddle releases and mags that have to be "rocked in" are slower than STANAG compatible mags and require more operations. Putting the charging handle on the right hand side requires you to reach over the top of the weapon to charge it.

    As for ammunition, the AK74's 5.45 is less accurate than it's western counterpart, while actually being less effective terminally in the short term(tissue death due to temporary cavity is irrelevant in this aspect, and even then the 5.56 does it better), it penetrates cover less effectively than 5.56 does(M855 ball and M856 tracer are both pretty decent penetrators), while being every bit as prone to overpenetration of sofft tissue as 5.56.

    If you went to the even more obsolete 7.62x39(out of the 47), you do gain penetration over the 5.56, at the cost of increased recoil, decreased accuracy(it's even less accurate than the 5.45), and massively decreased terminal effectiveness. Even the Russians abandoned this round, and that should tell you something when the same country that has been clinging to the same obsolete design for 60+ years drops something.

    Neither the 5.45 nor the 7.62x39 are more damaging than the 5.56 is, for the task at hand.

    Russian calibers are substandard for nearly all applications. Period.

    Ammunition commonality is important, even for specops. If you can't reliably get ammunition, you are up shit's creek without a paddle, and exotic calibers(say, China's new 5.8, or H&K's 4.6) and weapons that take different magazines and parts than the rest of your team has is a good way to end up up said creek.

    There's a reason any country who can afford to buy western arms uses them, and not russian weapons that were obsolete 40 years ago. And that's because Russian weapons are inferior in every regard(except cost).

  8. Well, I guess we'll never know for sure unless 4Aces gets back on here with more details. Of course, since you've all called him a liar he may not be so inclined. Or it could have been a tall tale and we'll not see him back. Until then, I'll give him the benefit of the doubt. I just don't think there is enough detail to draw any conclusions. It could very well have been a ricochet. Obviously, since the guy had an armored helmet of some kind and it was .50 round, it sounds like it's possible it was an accidental hit of some kind. As far as I know none of the current enemies of NATO troops are fielding .50 cal weapons as a matter of course. The closet thing I can of would be the Russian 12.7 mm and 14.5 mm MGs.

    Helmets are spall protection, (the best ones do meet level III-A, but hits by anything meatier than shrapnel or very light handgun rounds at shallow angles of incidence will generally result in traumatic neck injuries or worse).

    The 12.7x108 round fired by the DShK and similar deliver comparable energy to the .50 BMG, and for all intents and purposes somebody taking fire from them won't be able to tell them apart without being familiar with the sounds of both weapons firing. Somebody over there would be able to distinguish the difference, but for our purposes the difference is academic(they throw comparable velocities and energy).

    In addition, captured/loaned M2s are surprisingly available in that part of the world(a friend sent me back some pics from a-stan I'd be happy to link of about a dozen older model M2s rusting away in a scrap pile). It's obviously not as common as leftover Warsaw Pact hardware, but they are floating around.

  9. You can give the guy the benefit of the doubt, but that would make you a fool. People get grazed by bullets all the time and live. People get grazed in the helmet by bullets on occasion, and live. But those are small caliber bullets. The amount of energy imparted on the helmet at a 1deg angle of incidence, from 2000 yds, by a .50 cal is just shy of the same energy putting the muzzle of M16 up against the side of the helmet(at 90deg incidence) and pulling the trigger. It's not that the round was a "near miss" that's the problem. It's that the round supposedly hit with enough energy to result in "a stiff neck", but didn't kill him. The window between the two, as I've explained above, is less likely than me seeing Echo in a dress. If it hits the head, it's going to have enough energy to kill. If it misses, that's not a hit. Period.

    Ricochets straight backward that strike shooters are surprisingly common(typically the result of a range that's way too leaded up to be safe, and poor berm design, I've been hit by several in indoor ranges and refuse to shoot in them anymore because of it, that shit stings like a motherfucker), and lose energy rapidly. Ricochets that hit anything else are extremely uncommon. Unless he was shooting a fifty, on a square range, the likelihood of said hit remains pretty much nil(and if the poster had any measure of honesty, would have mentioned that it was a ricochet). So he's either outright lying, or (on an extreme longshot) he's stretching the truth intentionally(still lying in most people's books).

    The odds are so far against it that no sane person ought to consider him anything less than a liar.

    EDIT TO ADD:

    Which is more likely, that he saw somebody survive something this unlikely, or that he is, in fact, full of shit.?

  10. It's quite possible it simply grazed the side of the guys helmet. Rather than disbelieve the poster why don't you just believe the guy that got hit was extremely lucky due to whatever circumstances? Those things happen all the time in real life. I agree that information provided is very sketchy, too sketchy to draw any conclusions. That's why I said what I said.

    A hit on a shallow enough tangent to not snap the guy's neck, but still be notable as any kind of "took a hit" is such a tiny area that it's effectively not going to happen. It's about as likely as your "maybe the round fizzled". The line between "hit" and "miss" with .50 cal works out to be under an eighth of an inch. So no, they don't happen "all the time" or even close. Lighter rounds yes, but once you start throwing around that much weigh, the likelihood shrinks to nigh impossibility. The information provided showed quite a lot(an approximate range, that the person claimed he saw it firsthand, the poster's ignorance). So I'm not inclined to give the benefit of the doubt to somebody who doesn't even know what their issued helmet is made of(Echo, care to chime in on if that is taught formally?).

    This guy's story is about as likely as a man getting bitten by a great white, while being struck by lightning, twice, in the middle of a tornado. In Idaho. And I've heard way too many similar stories(always from people who can't prove that they even have a military background at all) from others in my line of work.

  11. Wow, that was unscientific. Apparently you didn't read the original post. If you'll actually take the time to read it, you'll see that the facts are VERY sparse. They don't even know where the bullet came from, therefore, your numbers and assumptions are useless.

    They don't know how far it was, but had an approximate. So to be safe, I used /twice as far/ as their approximate. Angle is largely irrelevant to this provided it strikes secantially or directly, while a tangential impact will have progressively decreasing levels of energy imparted, excepting that a tangential impact in this case is going to put a hole in that guy's head anyway(even at 2000yds, that bullet has enough energy to hole both sides of the helmet at ANY angle), and even assuming an infinitely strong helmet will exert enough energy rotationally to twist and snap the neck. Of course, the figures above are completely ignoring that the helmet would have been compromised and his head pulped, by assuming an arbitrarily strong helmet.

    I tried to give the target every possible advantage, assuming a range twice the estimate, a secantial impact and an infinitely strong helmet and it still results in a fatal impact regardless, either through the helmet being compromised OR through traumatic head and neck injury.

    Of course, if the individual actually was telling any manner of truth at all, they would have known that there aren't any "plates" in a helmet, and that anything inside of two miles with a .50 won't be "pretty slow". Being "sparse with details" doesn't count in your favor when you're making blatantly impossible claims and showing massive amounts of ignorance of things you'd be educated on if you were actually in the military.

    I did do my calculations for 1 degree of incidence, on the secant. Anything more aggressive than that is going to put a hole in the target's head. Literally anything that strikes the helmet with the full diameter of the bullet at that velocity and energy is going to be almost three times as much as required to snap the neck. If it doesn't strike on the secant, but rather on the tangent, unless it strikes on an absurdly low percentage of the frontal area, it's going to have more than enough energy to again snap the neck(or penetrate the helmet). Lighter rounds are readily deflected by a helmet, but when you're throwing that much around, you're exceeding the amount the spine can handle.

    We don't know for sure, but when a person claims "1km away", that means they at probably have an idea of the distance to the contact, even if it is't precise. To give him the benefit of the doubt, I gave it twice the range, which is significantly reduced energy and velocity from 1km(as you can see).

    Somebody speaking out of complete ignorance(again, I point to plates in a helmet) is a pretty good sign they're full of crap, especially when they throw in "I saw somebody" as a vagarie, and when people start making such claims, the burden of proof is on them. A more important question might be why you're going so far out of your way to defend somebody who is telling some really tall tales, with really sketchy information.

  12. "It's not good to lie to people, dude."

    It's not good to call people liars without all the facts either.

    Normally, I would agree that a direct hit, square on, from 1 km, in the head from .50 cal probably would kill anyone no matter what kind armor they were wearing, but it's wrong to call him a liar unless you know all the facts. First of all, he was guessing about how far it came from ("assumed to have been fired from about 1km away"), second we don't know the angle of impact. A graze could have just about zero energy transferred. Finally, we don't know if the round had already impacted something on the way (reducing the energy greatly.) It's also possible the round could have been a fizzle too.

    Echo summoned me for this thread(I'm a gunsmith and ballistician, the neuroscientist to Echo's neurosurgeon, if you will). I live and breathe this shit.

    I'll run these figures assuming Barret's .50BMG data(velocity, weight, BC, etc.) are correct to start with. Finding reliable data for velocity out of an M2 or DShK is nigh impossible(and I don't have one), so I'll estimate from minimums(M82CQ with a 20" barrel).

    Round is 661gr with a BC of .611

    Muzzle: 9174ft/lbs @ 2500fps

    500yds: 4980ft/lbs @ 1842fps

    1000yds 2596ft/lbs @ 1330fps

    1500yds: 1533ft/lbs @ 1022fps

    2000yds: 1148ft/lbs @ 884fps

    So, even assuming that the round came from 2000yds(which is ridiculous, you'd have trouble even seeing a person or small group of people unaided at that range in any kind of practical environment), it's packing almost as much energy as a .223 has at the muzzle. That is a positively massive amount of force(more than it seems like), even on a graze. Modeled as an elastic collision(the most beneficial way to model it for the survival of our hypothetical soldier) using a 3lb helmet and figures for 2000yds we get final (rounded) velocities of:

    830fps for the bullet

    54fps for the helmet

    3lb helmet moving at 54fps = 135ft/lbs of energy imparted to the skull by the helmet. This energy has to go somewhere, and that somewhere is the head and neck of the target. Pulling some figures from another individual calculating bullet/head impacts(specifically JFKs) regarding spinal cord injury

    Placing several persons supine with the head resting on bathroom scales resulted in an average range of 8 to 10 lbs. An assumption of 15 to 20 lbs for the head neck mass appears more realistic than 34 lbs. I suspect that mid-neck severed heads weigh about 15 lbs but I do not know of any corner studies confirming this. An accurate estimate of the head neck mass is essential to the calculations.

    [using 15 lbs, E=(½ x 15)(1.8)2 = 24.3 foot-pounds, using 26.5 lbs, E=(½ x 26.5)(1.8)2 = 43 foot-pounds, using Wilber’s 34 lbs, E=(½ x 34)(1.8)2 = 55.08 foot-pounds required to move the head as seen in the Z film

    - http://karws.gso.uri.edu/JFK/Issues_and_evidence/Frontal_shot%28s%29/Tobias_frontal_shots/Head_snap.html The bulk of this text is irrelevant for other reasons(such as calculating how much force was imparted to JFK's head to result in the neck snapping motion and rebound back and to the left), but the math works out and it's a good indicator for how far the head would have had to travel to result in traumatic injury to the spinal cord.

    In conclusion, even assuming the helmet DID survive the impact(the angle of incidence was low enough to not be penetrated by the bullet, by some miracle), and assuming that the helmet didn't move against the head during the impact and impart even further force to the skull, the "friend"'s neck would have been snapped, and he would likely have died or been paralyzed for life.

    ...so yeah, I'm calling bullshit. If you or Echo would like me to calculate energy of the bullet after striking something hard, ricocheting and hitting the target, I can, but the result is largely irrelevant to the issue at hand(it will still be more than double the required amount).

    Thank you for your time,

    Paul

    P.S. - Ammunition seldom "fizzles". And by seldom, I mean "doesn't happen", at least not in the manner described. When ammunition malfunctions, it is typically either due to age and poor storage(in which case it may hangfire due to bad primers, squib due to nonfuctioning powder or just not fire at all due to bad primers again) or due to poor quality control during manufacture (which due to how the machines work, does not result in light charges, but rather no powder or even rarer a double charge, resulting in either a squib or pressure damage respectively).

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