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Phanatic posted:That's the other 10%. If that's all you were going for you could just build a wider flight deck, without an extra set of cats, and use the extra space to park aircraft so the recovering aircraft aren't headed right for them. I'm sure the shipwrights would be very interested to hear how easy making the deck much wider would be, especially if you wanted edge elevators still. I'm pretty sure the CdG class actually has an active stabilizer so the ship's sides don't move to far vertically as it pitches because of its proportions.
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# ? Sep 13, 2016 16:27 |
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# ? May 25, 2024 15:06 |
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xthetenth posted:I'm sure the shipwrights would be very interested to hear how easy making the deck much wider would be, This was the USS Midway as launched: This was the USS Midway as retired: If you can weld an entire angled flight deck onto a carrier that wasn't designed with one, adding nearly 100' of beam, you can definitely just design the ship with an offset parking area in the first place. But doing *that* doesn't let you launch and recover at the same time, which is why instead of doing that we designed ships with angled flight decks.
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# ? Sep 13, 2016 16:45 |
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feedmegin posted:Did they not distinguish between direct-fire and indirect-fire pieces, then? The engineers/designers did, but both assault guns and tank destroyers were lumped into the "SPG" category and were treated as artillery and not tanks when it came to organization and design.
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# ? Sep 13, 2016 16:58 |
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How tricky is it to set a direct fire tank, say, to fire in an indirect role? If you are sufficiently desperate, I mean? Can't you just get out the protractor and a plumb-bob, and use a calculator?
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# ? Sep 13, 2016 17:15 |
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Phanatic posted:This was the USS Midway as launched: Looks like they moved all the elevators too.
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# ? Sep 13, 2016 17:17 |
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Yeah, edge elevators are a big deal. How are you going to have that port elevator if you're scabbing on another runway width right through there? Never mind that you aren't touching down on the centerline of the ship, which is going to suuuuuck for rough weather ops.
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# ? Sep 13, 2016 17:21 |
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Fangz posted:How tricky is it to set a direct fire tank, say, to fire in an indirect role? If you are sufficiently desperate, I mean? Can't you just get out the protractor and a plumb-bob, and use a calculator? A lot of tanks were designed for it, and have stuff like azimuths and elevation markers for after-hours artillery work, but even things that weren't remotely intended to be artillery got used for that role. Tank destroyer divisions fired something like four or five times more indirect rounds than they fired direct and I can't imagine shermans, stugs or T-34s avoided doing the same. Hell, wasn't the Raisenai KV-1 firing indirectly when it was accosted?
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# ? Sep 13, 2016 17:26 |
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Fangz posted:How tricky is it to set a direct fire tank, say, to fire in an indirect role? If you are sufficiently desperate, I mean? Can't you just get out the protractor and a plumb-bob, and use a calculator? It was really common in WW2 and Korea, but modern tanks (at least in the US) don't do it at all...the guns can't elevate enough, they don't use HE rounds, and the firepower of a tank's main gun is pretty puny compared to a modern howitzer or mortar.
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# ? Sep 13, 2016 17:29 |
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Fangz posted:How tricky is it to set a direct fire tank, say, to fire in an indirect role? If you are sufficiently desperate, I mean? Can't you just get out the protractor and a plumb-bob, and use a calculator? Probably quite hard given that normal tanks don't have the gun elevation required to shoot indirectly, or necessarily the ammunition. It would be like doing indirect fire with a machinegun, technically possible but probably not very useful.
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# ? Sep 13, 2016 17:35 |
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OwlFancier posted:Probably quite hard given that normal tanks don't have the gun elevation required to shoot indirectly, or necessarily the ammunition. The elevation problem was fixed by digging a sloped hole and backing into it or just using a handy hill as a ramp. Google around and you'll find tons of photos.
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# ? Sep 13, 2016 18:06 |
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Cyrano4747 posted:The elevation problem was fixed by digging a sloped hole and backing into it or just using a handy hill as a ramp. Google around and you'll find tons of photos. Yes indeed, like so:
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# ? Sep 13, 2016 18:11 |
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Surely a mortar team would be more effective?
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# ? Sep 13, 2016 18:26 |
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OwlFancier posted:Surely a mortar team would be more effective? Sometimes you just don't have mortars on hand.
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# ? Sep 13, 2016 18:27 |
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OwlFancier posted:Surely a mortar team would be more effective? Also, not instead of.
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# ? Sep 13, 2016 18:27 |
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OwlFancier posted:Surely a mortar team would be more effective? I'm pretty sure you do that when you don't have other poo poo available.
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# ? Sep 13, 2016 18:27 |
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Maybe but a lot of stuff like that is determined by what you have on hand not what would be optimally efficient. Also who is to say mortars weren't in use? What is better, using only mortars or mortars plus those tanks that would otherwise be idle at that moment?
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# ? Sep 13, 2016 18:28 |
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Plus, the M1 only had an effective range of 3,000m - I sort of assume a rifled tank gun in an indirect fire role can reach out a bit further.
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# ? Sep 13, 2016 18:30 |
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spectralent posted:A lot of tanks were designed for it, and have stuff like azimuths and elevation markers for after-hours artillery work, but even things that weren't remotely intended to be artillery got used for that role. Tank destroyer divisions fired something like four or five times more indirect rounds than they fired direct and I can't imagine shermans, stugs or T-34s avoided doing the same. Hell, wasn't the Raisenai KV-1 firing indirectly when it was accosted? T-34 ballistic tables contained angles way beyond the gun's actual ability to elevate, so presumably they would fire from a slope. I've seen photos of Priests firing from wooden beams that sloped them backwards to increase elevation. OwlFancier posted:Probably quite hard given that normal tanks don't have the gun elevation required to shoot indirectly, or necessarily the ammunition. I've read about it being done several times. You're right, it wasn't particularly useful.
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# ? Sep 13, 2016 18:32 |
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It is sort of an interesting early example of the "multifunctional" capability that everyone is so enamored with nowadays. It is always funny to me how many historical examples there are of CUTTING EDGE FUTURE CONCEPTS
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# ? Sep 13, 2016 18:39 |
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KYOON GRIFFEY JR posted:Plus, the M1 only had an effective range of 3,000m - I sort of assume a rifled tank gun in an indirect fire role can reach out a bit further. The M4 would be pretty comparable to the 1897 75mm howitzer most likely. The three inch guns would likely have better range than light howitzers.
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# ? Sep 13, 2016 18:42 |
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Ensign Expendable posted:I've read about it being done several times. You're right, it wasn't particularly useful. The thing I read about the tank destroyers, at least, was that they (and presumably the shermans) were liked in an improvised artillery role because they were almost as good as proper howitzers but didn't crater the roads so much.
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# ? Sep 13, 2016 18:47 |
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It's still surprising they'd go to all that effort, I wouldn't have thought a 75mm shell would be especially effective at long range, accounting for dispersion and that.
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# ? Sep 13, 2016 18:49 |
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75mm (or 77, or 3-inch) artillery has historically been quite effective.
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# ? Sep 13, 2016 18:51 |
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OwlFancier posted:It's still surprising they'd go to all that effort, I wouldn't have thought a 75mm shell would be especially effective at long range, accounting for dispersion and that. You're not shooting at point targets with a single gun. You get your whole platoon lined up and put rounds on an area target. In that use the dispersion of individual tubes is a feature not a problem. Point fire on specific called targets is what direct fire is for in which case you drive the tank out of the hole and use it as a tank.
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# ? Sep 13, 2016 18:58 |
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JaucheCharly posted:I'm a bit out of the loop, but Mark Stretton did some testing I'll preface this post to say my initial paragraph in this post was just reading the blog entry, but then I scrolled down and got Mad On the Internet. I can't be arsed to make this flow well but here's the post as I've got it: He keeps talking about the plate being hardened or tempered but the holes don't look like what I would expect holes in hardened or even tempered steel to look like, but rather unhardened steel. He also mentions working the plate cold (in order not to spoil the temper) to close the holes he made, but tempered steel does *not* work cold well, especially after it has already been bent. Aside from the fact that his plate is too thin (the Avant armour is 3.2mm at its thickest and this guy's maxes out at 1.7mm) it's also not very globose, so he has a much better chance of getting a 90 degree or near-90 hit. He has no aketon underneath the armour, or indeed any real cloth whatsoever, which would significantly impede penetration of such a wide point. Hell, he doesn't even account for the energy expended by the arrow in deforming the armour in the first place. I read further into the blog and this guy is completely off his loving nut. This post in particular just completely misunderstands blunt trauma: http://markstretton.blogspot.com/2016/05/does-arrowhead-need-to-penetrate-armour.html?m=1 He acknowledges that armour distributes impact then completely ignores this to conclude that archery was an instant kill, or at least debilitating with every impact on the head or even the drat body. He doesn't understand or ignores the difference between impact on the body in a small or wide area. There is no mention of padding whatsoever. So because of all this and some trauma study which he only knows of 4th hand, he concludes that 80J of impact is enough to kill. So those men-at-arms I mentioned earlier, getting hit on the tops of their bascinets? They were actually dead. Henry V? Died at Shrewsbury. Gutierre Diaz de Gamez when he wrote El Victorial? Dead. The French couldn't have won the HYW because they had all died from >80J impacts. He also doesn't seem to understand how that energy translates into force, which is mass x acceleration and is more important for understanding trauma through armor. So let us assume that an arrow uses all its force on an armored target in .01 seconds.This gives us 610 newtons of force. We reach this number with the very generous qualifications that that the helm was not moved backward by the impact, no deformation of the armour, no padding, and a 90 degree impact. We are shooting a human head (about 4.5kg on the lower end of average) wearing this sallet. So the overall weight we're working with is 6.3 kg. Those 610 newtons will move the head and helm with 9.9 Gs of acceleration, assuming the acceleration is perfectly linear. Note we're not factoring in any of the impact taken by the rest of the body via the neck. This is not only well below under the lowest concussive impact in this article(60.51 g), but is below even the only semi-reputable subconcussive impact threshold I can find of 20 Gs (we're essentially guessing at the threshold right now). So if your arrow doesn't go through the armour you won't kill him, you won't concuss him, but maaaybe he'll get depression some day Here's a slightly TLDR version to give a good illustration of how energy and force differ. Mark notes that a hammer swung at 12m/s would need to weigh 5 lbs (2.25kg) to have the same energy as these arrows. But compared to their 610 Newtons, such a hammer would give you over 2000, assuming the same deceleration on impact.
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# ? Sep 13, 2016 19:02 |
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OwlFancier posted:It's still surprising they'd go to all that effort, I wouldn't have thought a 75mm shell would be especially effective at long range, accounting for dispersion and that. I have an officer's manual from 1940 that has 21 pages detailing the indirect use of medium machineguns, including ballistic formulas and tables, wind correction tables, ammo consumption for effect etc. etc. For instance, to achieve 50% losses to a target 2.5km away spread across an area 100 metres wide, 50m deep you need to fire 4300 bullets. If the same 100m wide target area has no depth (a straight line, eg. a trench) you need 2600 shots for the same effect. For 50% probability of hitting a standing man at the same distance you need 800 shots. So yeah, armies will go through any effort to kill a dude or force the dude to bugger off or stop him from approaching some place that they don't want that dude to reach, such as barrages on roads to hinder troop movements. And especially for that purpose all guns are good enough, you just don't drive a truck through a crossroads being shelled or pelted with machinegun fire. Assuming the fire is accurate, which especially for machinegun fire is hard to discern. Against entrenched defenders it might not be much, but suppression can be enough. Also, counter-battery fire is not an issue.
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# ? Sep 13, 2016 19:19 |
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quote:So let us assume that an arrow uses all its force on an armored target in .01 seconds.This gives us 610 newtons of force. I think 0.01 seconds is a huge overestimate. Consider an arrow travels at 200-300fps, and so averages during deceleration 100-150fps. This means that during their deceleration, you're saying the arrow travels 1-1.5 feet! This isn't an arrow that bounced off any more, this is an arrow that had gone through the poor guy. Divide the distance of deceleration by 10 and you multiply the gee force by 10. Suddenly the situation looks a lot more reasonable to me. Edit: try the following thought experiment. Imagine you are throwing the hammer/firing the arrow at a spring. When the hammer/arrow is stationary, then all the kinetic energy has been transferred into the spring - this means the spring must have compressed by the same amount! Then if you use the formula Work done = Force x Distance You must conclude that the force exerted by the two objects must be exactly the same. What does alter is time this all takes and the rate of deceleration - it all happens a lot faster with the arrow. (Insert relevant disclaimers about how comparable a head on a neck is to a spring, but I don't think it's terrible.) Fangz fucked around with this message at 20:02 on Sep 13, 2016 |
# ? Sep 13, 2016 19:25 |
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Cyrano4747 posted:You're not shooting at point targets with a single gun. You get your whole platoon lined up and put rounds on an area target. In that use the dispersion of individual tubes is a feature not a problem. I know, I just mean that I wouldn't have thought with the presumed desire for long range and the limitations of the caliber, and the fact that you're presumably firing tank-grade HE rounds rather artillery rounds which are presumably longer and have larger charges, that the actual effect at the far end would be rather minimal? Like even if it's all you have you're still spending munitions and time the tanks could spend doing something else digging them into firing positions and that. Just surprises me that people went to the effort. Nenonen posted:I have an officer's manual from 1940 that has 21 pages detailing the indirect use of medium machineguns, including ballistic formulas and tables, wind correction tables, ammo consumption for effect etc. etc. For instance, to achieve 50% losses to a target 2.5km away spread across an area 100 metres wide, 50m deep you need to fire 4300 bullets. If the same 100m wide target area has no depth (a straight line, eg. a trench) you need 2600 shots for the same effect. For 50% probability of hitting a standing man at the same distance you need 800 shots. I genuinely didn't think indirect machinegun fire actually worked because I thought the rounds lost too much velocity over that sort of range. I recall it was supposedly done in the first world war but I didn't think it continued past that. OwlFancier fucked around with this message at 19:31 on Sep 13, 2016 |
# ? Sep 13, 2016 19:29 |
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feedmegin posted:Did they not distinguish between direct-fire and indirect-fire pieces, then? While they were most likely designed to do so, it didn't end that way in practice all the time. In Italy, M10s commonly took over as indirect fire artillery. And if it was safe for an artillery SPG to do so, they'd just go ahead and engage in direct fire. Even the Sherman variants had sight arrangements for indirect fire, which pretty much anyone who used them appreciated. The names didn't define roles so much. Tank destroyers' official names almost always ended with "Gun Motor Carriage," (same as SPG) but their roles were usually "tank destroyer" since they were literally designed as anti-armor vehicles and issued only to tank destroyer units. It wasn't always consistent, though. If I remember right, most artillery SPGs had GMC in the name, with a handful of them like the M7 were called Howitzer Motor Carriages, but their intent didn't differ. Plan Z fucked around with this message at 19:38 on Sep 13, 2016 |
# ? Sep 13, 2016 19:36 |
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OwlFancier posted:I genuinely didn't think indirect machinegun fire actually worked because I thought the rounds lost too much velocity over that sort of range. No "supposedly" about it, mynheer, it's an excellent way of laying down suppressive fire at targets who are less than about 800 yards away. You don't need to kill them or hit them, just keep them suppressed until the blokes can get in among them with the bayonet.
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# ? Sep 13, 2016 19:48 |
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OwlFancier posted:I genuinely didn't think indirect machinegun fire actually worked because I thought the rounds lost too much velocity over that sort of range. Range is not an issue, human beings are quite squishy and it doesn't take that much energy from a piece of metal to perforate you. OTOH if your target is behind some type of cover then the effectiveness drops rapidly. The biggest weakness with this is that a spotter is unlikely to tell if the fire is hitting the target area or to give accurate corrections. But if it's the only way your machinegun company can support a battle, then why not? In one account that I read, supporting machineguns were ordered to fire at tree tops around the defender's location for demoralizing effect because the dense forest terrain was otherwise useless for them. This was in 1941 Finnish army attacking Soviets.
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# ? Sep 13, 2016 19:52 |
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Rodrigo Diaz posted:I'll preface this post to say my initial paragraph in this post was just reading the blog entry, but then I scrolled down and got Mad On the Internet. I can't be arsed to make this flow well but here's the post as I've got it:
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# ? Sep 13, 2016 19:52 |
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JaucheCharly posted:Told ya, it's lacking and you're also a sperglord. As I said earlier, the physics is wrong in this post.
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# ? Sep 13, 2016 19:55 |
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Fangz posted:I think 0.01 seconds is a huge overestimate. Consider an arrow travels at 200-300fps, and so averages during deceleration 100-150fps. This means that during their deceleration, you're saying the arrow travels 1-1.5 feet! This isn't an arrow that bounced off any more, this is an arrow that had gone through the poor guy. Thanks for the correction, your point is a good one. Stretton says the arrow was travelling at 48.8 m/s, so maybe more like x5 rather than x10? That leaves it in the subconcussive range, but still, that is with circumstances highly favorable to the bow.
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# ? Sep 13, 2016 19:57 |
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Indirect machine gun fire was big in ww1 due to the newness of the weapon and the relative static nature of the war. They were generally very effective in the indirect role. Indirect is still a thing in machine gun pubs, though it isn't used often as previously noted. Understanding the beaten zone is still a big deal though, due to it's usefulness in situations with difficult terrain. Sample use of machine guns in the indirect role: in one attack, the American 29th division used its machine gun battalion, specifically four batteries of four to six machine guns with designated zones of fire, set up parallel the avenue of attack to achieve a beaten zone of 100x100m (per gun). It was essentially a rolling barrage and was the primary form of indirect fire supporting the attack (though there was some artillery in support) FastestGunAlive fucked around with this message at 20:11 on Sep 13, 2016 |
# ? Sep 13, 2016 20:08 |
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Nenonen posted:Range is not an issue, human beings are quite squishy and it doesn't take that much energy from a piece of metal to perforate you. OTOH if your target is behind some type of cover then the effectiveness drops rapidly. As in, I thought that they actually lost velocity sufficiently that they became non-lethal, like being pelted with metallic hailstones. Though I may be conflating that with some insane idea to fire up into the air to drop rounds into the trench.
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# ? Sep 13, 2016 20:25 |
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OwlFancier posted:I know, I just mean that I wouldn't have thought with the presumed desire for long range and the limitations of the caliber, and the fact that you're presumably firing tank-grade HE rounds rather artillery rounds which are presumably longer and have larger charges, that the actual effect at the far end would be rather minimal? Well, consider that the 76mm and 85mm used by the T34 used the same ammo as their standard 76mm and 85mm field guns.
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# ? Sep 13, 2016 20:29 |
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OwlFancier posted:As in, I thought that they actually lost velocity sufficiently that they became non-lethal, like being pelted with metallic hailstones. Takes a really long range for them to do that. HMG rounds are lethal out to well over 2000 yards, even .30 MGs are effective out past 1000.
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# ? Sep 13, 2016 20:34 |
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Trin Tragula posted:No "supposedly" about it, mynheer, it's an excellent way of laying down suppressive fire at targets who are less than about 800 yards away. You don't need to kill them or hit them, just keep them suppressed until the blokes can get in among them with the bayonet. While I wouldn't press Flames of War as an amazing treatise on period warfare this is why British MG platoons are great even though you can't dole them out to infantry platoons. It's like a lovely mortar barrage while you run your tommies into a wall of MG42s
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# ? Sep 13, 2016 20:47 |
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# ? May 25, 2024 15:06 |
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During Vietnam the 101st Airborne used M2 .50 cals in indirect fire roles (Especially Quad .50s) a lot in the Central Highlands to sweep the reverse slope of hills around firebases where the NVA liked to put mortars. Ripcord by Keith William Nolan covers it pretty well.
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# ? Sep 13, 2016 20:59 |