Light-gas guns at the Arnold Air Force Base's Hypervelocity Ballistics Ranges. Used extensively in hypervelocity and impact research, the guns fire projectiles at extremely high velocities.
Fullsize image: https://s3-us-west-1.amazonaws.com/h...n_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...ht_gas_gun.jpg
Previously:
https://www.homemadetools.net/forum/...566#post158971
