Los Alamos Guns

Warning, discursive contribution including description of naked women.

I noted that the breeches are sealed with a complete thread due to the high pressures, no Welin interrupted threads here.

True, if irrelevant, story.
I am lazy, when I search on the internet I use an abreviated search phrase and hope Google will do the work.
I expect many do the same.
So one day I type "wellin screw" (my error, with two lls) and press enter, no relevant matches so I select "images". My screen fills with naked women.
The phone rings, I take the call and return to the screen, where SWMBO now is.
Was my explanation believed? No.
Apparently Holly Wellin, who was in the images is a well known porn star.

But why, o why, do they start the film with a man in a baseball cap chewing gum? Because this, in my opinion, makes one look stupid

JHOLLAND1 said:

https://www.youtube.com/watch?v=Zhxtckcti40

Click to expand...

Interesting experiments, but rather poorly made video.
On a few occasions I was working with Los Alamos groups, but only on ion sources and accelerator targets. I did not know they do ballistics experiments.

billzweig said:

Interesting experiments, but rather poorly made video.
On a few occasions I was working with Los Alamos groups, but only on ion sources and accelerator targets. I did not know they do ballistics experiments.

Click to expand...

Watch it again. Their compressing hydrogen in the barrel. That's used for making buckets of instant sunshine.

The hydrogen compressing experiment is called a "ballistic compressor". I worked with one many years ago which used a fast-acting valve to let compressed N2 at 2500 PSI drive a heavy (tungsten) piston down a barrel. The drive gas accelerated the piston over a long distance, doing "work' on it and imparting kinetic energy to it.

Ahead of the piston was the "test gas". The kinetic energy of the piston compressed the test gas to as much as 200,000PSI (it ended up in a VERY thick-walled chamber at the end.

Obviously, since energy in==energy out, the mass of gas at 2500 PSI used to accelerate the piston had to be much greater than the mass of the test gas, for the final pressure of the test gas to be so much higher.

You could get similar pressures from direct burning of explosive propellants, but the ballistic compressor gives you smoothly rising pressure in clean gas of your chosen composition. Seems the BC at los Alamos used gunpowder as its propellant.

I designed some parts of the BC we used, and the boss initially said the piston was to be made of depleted Uranium. Our client, some part of the DOD, would provide it. They like to specify it so as to use up the otherwise merely useless and dangerous by-product of the making of bomb materials. It was dense, would make a heavy piston. I said if there was going to be a chunk of U in the building I was going to get a job somewhere else. So I suggested tungsten instead, as denser even than U, stronger, machinable, harmless. We had it brass-plated lest it gall in the barrel.

magneticanomaly said:

...I designed some parts of the BC we used, and the boss initially said the piston was to be made of depleted Uranium.... I said if there was going to be a chunk of U in the building I was going to get a job somewhere else...

Click to expand...

Tungsten was a better choice. For applications where high density is needed, uranium offers no advantage over tungsten (and uranium has poor corrosion resistance to boot), but it is an excellent neutron absorber and is used as neutron blockers in some applications. Depleted uranium is actually quite safe to work with and machines well.

I'm glad to read that Billz, as I have a long rod penetrator projectile feet away from where I sleep.
It looks so cool, fin stabilized and the whole story that goes with every one. the ratchet shaped energy transfer grooves along the body, and of course the flare in the base. Who thinks up this stuff? So devious and destructive.

Thanks for the interesting video!