https://www.quora.com/Will-rai...youtu.be/58MmOpSm4LY
If you are not trying to go above Mach 2 or 3, and with battery tech getting better, are we within a dozen years of a sporting railgun? Anyone have a science project due and want to make a prototype
No more powder or brass or primers...just sabots and projectiles. Imagine no need for ear protection.
I think a 12 bore rail gun with the goal of traditional velocities and lever action/black powder velocities would be a great starting point. I may need to call up Elon Musk and ask him for some batteries. Hey, he made a flame thrower! He may want to make small arms rail guns!
Now how much electricity is needed to propel a 1 ounce slug at 1,200 fps?
Saeed! I got a great investment opportunity for you! Walter can be the CEO. Battery powered guns are the future! It may require a backpack battery for now.

Time for a blaser tesla team up

Mike

I'd like to see Heym make a double rail gun
Tesla has those home system batteries that could be worn as a backpack. Maybe instead of a gun bearer, you could have a battery bearer

It won't happen, at least with normal barrel length or bullet travel.

Even if the bullet has the same rate of acceleration from rest to muzzle you simply won't have anywhere near the horsepower required.

1 horsepower is lifting 550 pounds 1 foo in 1 second or 55 pounds 10 feet in 1 second or 33,000 pound 1 foot in 1 minute.

If we use the 550 pounds 1 foot in second that is 550 ft/lbs of energy (work) in 1 second. Now let's say our rifle has a muzzle energy of 3300 ft/lbs. If we lifted 3300 pounds 1 foot in 1 second we have 6 horsepower.

However, our bullet is getting to 3300 ft/lbs does it in a lot less than 1 second. If it gets from rest to the velocity to get to 3300 ft/lbs, say a 165 grain at 3000 f/s, if it took 1/1000th of a second from rest to 3000 f/s then that would require 6000 horsepower. Actually in our normal rifle the horsepower (rate at which work is done) would be far in excess of 6000 HP in the first few inches of bullet travel.

To the above you also have to factor in losses. For example if it takes 100 HP to accelerate a car to a given speed then because of losses you will need more than a 100 HP engine.

Hmmmmmm
I'll have to check your math and logic when I have a few hours.
Let's start small.
How about the just imagined S.S.S.S. (Silent Subsonic Sniper System)
Move a 300 grain high BC 338 bullet at 1050 fps.
That should be as silent as my wife's farts in church.
How much barrel and battery is needed for that?

If that is too much, then we can go down to pistol power.

quote:

Originally posted by boom stick:
Hmmmmmm
I'll have to check your math and logic when I have a few hours.
Let's start small.
How about the just imagined S.S.S.S. (Silent Subsonic Sniper System)
Move a 300 grain high BC 338 bullet at 1050 fps.
That should be as silent as my wife's farts in church.
How much barrel and battery is needed for that?

If that is too much, then we can go down to pistol power.

It is really very simple.

Let's take 300 grain 338 at 1050 f/s. That is about 730 ft/lbs. Since you have said a 'small arms" and also in context of the forum then we are talking about 2 feet of bullet travel. So you have do 730 ft/lbs of work in that 2 feet of travel. Even at 1050 f/s the time is small in the extreme. With even rate of acceleration if we thus averaged 525 f/s for the 2 feet of bullet travel. So it will take the bullet 2/525 = 004 seconds. So you have to do 730 ft/lbs of work in .004 seconds.

Don't worry about the battery. Let's just say you can have all the electricity you want …… then what are you going to do with the electricity? Purely for the exercise we will assume your "rifle" can be the same size and weight as a Mark V 460.

Think of this way. Your barrel is a drag strip and there is the problem, your drag strip is only 2 feet long.

https://www.youtube.com/watch?v=fKEaDhDTciQ

quote:

Originally posted by 4sixteen:


https://www.youtube.com/watch?v=fKEaDhDTciQ

Good idea to use the capacitors. With points and coil ignition we always called them the condenser.

How about a 12' coil shaped barrel to make it more compact?

quote:

Originally posted by boom stick:
How about a 12' coil shaped barrel to make it more compact?

If you watched the full video you will of seen that what they finished with was low powered, very lower powered.

Someone who knows a lot about magnetic fields and so on can be correct me here but you are also going to be limited by the projectile itself. For example, if you stick a pin on a small magnet or a powerful magnet the attraction will be the same although the more powerful magnet will attract the pin from further away.

To look at the rifle another way and instead of horsepower consider a calibre using 70 grains of powder. If that takes 1/1000th of a second to burn (and most of it will have gone in far less time) then if it was continuous you would be burning 70,000 grains, 10 pounds, per second, 36,000 pounds per hour.