11-19-2019, 07:00 PM | #31 | ||
Join Date: Jul 2008
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Re: Different Gyroc Designs
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Though that would mean that the barrel isn't pointed straight at the target... Quote:
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11-19-2019, 07:14 PM | #32 |
Join Date: Feb 2016
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Re: Different Gyroc Designs
600 yards/second is a little low for high speed rounds. A 50 BMG (a 12.7mm round) goes over 1,000 yards/second while the 220 Swift (a 5.7mm round) goes over 1,400 yards/second. Faster speeds are known for tank guns and artillery.
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11-20-2019, 04:57 AM | #33 | ||
Join Date: Aug 2004
Location: Wellington, NZ
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Re: Different Gyroc Designs
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Secondly, you adjust the sights on your rifle such that the bullet follows a parabolic trajectory and that this trajectory peaks at some known maximum, probably +5 inches for a weapon intended for shooting humans. That means that from 0 yards out to t he point where the bullet has dropped to -5 inches you know that a shot at heart level is going to go into the lungs, heart, or liver, etc. So, yes it's accounted for, true. But not on the battlefield unless you're trying for head shots past a couple opf hundred metres. And, by the by, outside 200m is longish range for a firefight with small arms, and part 400m is definitely long range (call in some artillery). Quote:
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11-20-2019, 10:45 AM | #34 | |
Join Date: Feb 2005
Location: Berkeley, CA
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Re: Different Gyroc Designs
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Note that not knowing the range is also a problem against moving targets, and against fast moving target it's a very large problem. If you're shooting at passengers in a vehicle moving at 30 mph (44'/s), it only takes about a 0.02s error in estimated travel time (corresponding to 10" lateral displacement) to completely miss. |
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11-20-2019, 11:33 AM | #35 | |
Join Date: Jul 2018
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Re: Different Gyroc Designs
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There are other issues with faster: the higher the velocity the more propellant (or the more energetic/hotter your propellant needs to be unless you can somehow emulate a light gas gun) and that can mean more recoil/heavier and larger round and/or wearing out your barrel and increased heating. .220 Swift has a case nearly as large as 7.62 NATO for example. Tank guns have a propellant charge as heavy as the projectile itself and that cuts down EFC life by several times easily compared to HE/HE-Frag. There also seems to be some actual difference performance/efficiency wise when it comes to velocity and propellant (propellant for 5.56 NATO is like 35-40% of total recoil impulse, whereas with 7.62 mm - both kinds - it can be closer to 25%) I also think the .220 swift is only going to get the velocities you claim if you use a lighter bullet (2.5-3 grams I think, vs 5.56 NATO's 4 grams for M855A1. Heck the old M262 was heavier despite a lower velocity and the US military I've read tested 5.56mm rounds as heavy as 100 grains.) light but fast bullets have drawbacks over slower but heavier in terms of external (and in some cases, terminal) ballistics. More velocity means more recoil, and that means a heavier rifle or a more complex rifle (recoil mitigation, which has alot of issues tied to it, like a Muzzle brake) or it means a lighter round (which can also have drawbacks.) Odd as it sounds, speed can be useful, but it isn't everything when it comes to firearms. Or tank guns. The US 120mm APFSDS actually went with a somewhat slower round (~1550 m/s vs ~1740 m/s with certain rounds I believe) than its european counterparts because they wanted a heavier round. Which for a given aspect ratio means a thicker (more rigid) penetrator but may also mean more length (which increases penetration in a monolithic KEP) |
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11-20-2019, 11:58 AM | #36 |
Join Date: Feb 2005
Location: Berkeley, CA
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Re: Different Gyroc Designs
More velocity is generally less recoil at the same energy levels (it's less bullet momentum, though inferior efficiency usually results in somewhat more from gas).
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11-20-2019, 01:04 PM | #37 | |||
Join Date: Jun 2013
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Re: Different Gyroc Designs
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I do agree that imp probably isn't appropriate. Quote:
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11-20-2019, 02:06 PM | #38 |
Join Date: Feb 2005
Location: Berkeley, CA
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Re: Different Gyroc Designs
That is a guided missile, you're just using the weapon's sights as your guide. As for practicality, the information is hard to communicate to the missile unless you use a laser to illuminate the target, in which case that's a laser guided missile.
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11-20-2019, 02:27 PM | #39 | |
Join Date: Jun 2013
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Re: Different Gyroc Designs
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It seems like it would mostly be additional cost to the weapon itself, with the gyroc only being marginally more expensive (it can communicate with the weapon it's within, and can adjust its angle of flight, but doesn't need the constant communication of a Guided round, or the ability to acquire and track the target of a Homing round). Of course, it may be that the situations in which this feature would be useful are too hectic for the shooter to actually make use of it.
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11-20-2019, 02:42 PM | #40 | |
Join Date: Feb 2005
Location: Berkeley, CA
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Re: Different Gyroc Designs
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