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Thread: Railgun projectile mass and materials and velocities of railguns

  1. #1 Railgun projectile mass and materials and velocities of railguns 
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    I've seen 1500-2400m/s quoted as the practical velocity railguns will achieve and I've also seen 6km/s quoted as the maximum a railgun/projectile can endure. Most of what I've read about railguns are along with these velocities but I've read about velocities of up to 16-20km/s as maximum velocity. And do you know what is the mass and density of usual railgun projectiles? I've read that they're made from tungsten/depleted uranium so that would suggest density of around 19 grams/cm^3. But tungsten/depleted uranium is quite rare when compared to let's say steel/lead that usual bullets are made of, so can railguns be modified to use projectiles made of normal bullet materials? And I've tried searching about the mass of the projectiles and have run into a few sites with sources questionable and they've so far come up with 2kg, 3,2kg, 4kg, 9kg and 18kg projectiles so are these masses consistent? And do you believe that in the future railguns can be shrank into handheld weaponry to replace the gunpowder powered projectiles?


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    Quote Originally Posted by Tyzuris Coronati View Post
    I've seen 1500-2400m/s quoted as the practical velocity railguns will achieve and I've also seen 6km/s quoted as the maximum a railgun/projectile can endure. Most of what I've read about railguns are along with these velocities but I've read about velocities of up to 16-20km/s as maximum velocity.
    IIRC the UK tested one at 4 km/ sec at Kirkudbright some 30 years ago.
    And ~4 km/ sec is, so far as I can tell, approaching the limit within the atmosphere. Faster than that and the projectile will start to melt from frictional heating. Outside the atmosphere, or carefully designed projectiles, will give you a different ball game.

    And do you know what is the mass and density of usual railgun projectiles? I've read that they're made from tungsten/depleted uranium so that would suggest density of around 19 grams/cm^3. But tungsten/depleted uranium is quite rare when compared to let's say steel/lead that usual bullets are made of, so can railguns be modified to use projectiles made of normal bullet materials? And I've tried searching about the mass of the projectiles and have run into a few sites with sources questionable and they've so far come up with 2kg, 3,2kg, 4kg, 9kg and 18kg projectiles so are these masses consistent?
    ANY material can be used - provided that there's also a conducting "pusher". Again, referring to Kirkudbright I think they used aluminium and a mass of 4 grammes.
    There's no set mass, nor set velocity: mainly because no one has yet "standardised" rail guns. And even once they ARE "standardised"... take a look at what calibre bullets are: anything from 5mm up to 15 (or even larger if you consider artillery pieces) - they're designed to do a specific job - hence they'll vary by application.

    And do you believe that in the future railguns can be shrank into handheld weaponry to replace the gunpowder powered projectiles?
    Unlikely for the foreseeable future. Power requirements would seem to indicate that the number of available shots for a given weight - and weight is all important for infantry weapons - would be limited. The guy might have a devastating weapon but once he's fired 5 (or 10 or whatever) times that's it.
    And I'm not sure that there'd be any advantage - other than the "cool factor" - to having railgun personal arms. Current rifles etc do the job quite well.


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    Quote Originally Posted by Dywyddyr View Post
    Quote Originally Posted by Tyzuris Coronati View Post
    I've seen 1500-2400m/s quoted as the practical velocity railguns will achieve and I've also seen 6km/s quoted as the maximum a railgun/projectile can endure. Most of what I've read about railguns are along with these velocities but I've read about velocities of up to 16-20km/s as maximum velocity.
    IIRC the UK tested one at 4 km/ sec at Kirkudbright some 30 years ago.
    And ~4 km/ sec is, so far as I can tell, approaching the limit within the atmosphere. Faster than that and the projectile will start to melt from frictional heating. Outside the atmosphere, or carefully designed projectiles, will give you a different ball game.

    And do you know what is the mass and density of usual railgun projectiles? I've read that they're made from tungsten/depleted uranium so that would suggest density of around 19 grams/cm^3. But tungsten/depleted uranium is quite rare when compared to let's say steel/lead that usual bullets are made of, so can railguns be modified to use projectiles made of normal bullet materials? And I've tried searching about the mass of the projectiles and have run into a few sites with sources questionable and they've so far come up with 2kg, 3,2kg, 4kg, 9kg and 18kg projectiles so are these masses consistent?
    ANY material can be used - provided that there's also a conducting "pusher". Again, referring to Kirkudbright I think they used aluminium and a mass of 4 grammes.
    There's no set mass, nor set velocity: mainly because no one has yet "standardised" rail guns. And even once they ARE "standardised"... take a look at what calibre bullets are: anything from 5mm up to 15 (or even larger if you consider artillery pieces) - they're designed to do a specific job - hence they'll vary by application.

    And do you believe that in the future railguns can be shrank into handheld weaponry to replace the gunpowder powered projectiles?
    Unlikely for the foreseeable future. Power requirements would seem to indicate that the number of available shots for a given weight - and weight is all important for infantry weapons - would be limited. The guy might have a devastating weapon but once he's fired 5 (or 10 or whatever) times that's it.
    And I'm not sure that there'd be any advantage - other than the "cool factor" - to having railgun personal arms. Current rifles etc do the job quite well.
    Just to ask about how feasible would a nine meter long railgun that fires a 35kg tungsten shell at 1500 meters/second shell be?
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    I've read of some experimental railgun accelerating a projectile to 16km/s and one internet article IIRC said that 16km/s is the maximum a railgun can fire a projectile without the g forces destroying the projectile.
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