I got at least four shots using one of those when I went through basic in the Air Force.
nope, the technology didn’t change they completely abandoned it (The FDA revoked its approval). Now when you go through basic training they give you a shit load of injections the old fashion way.
there’s really no way to take one of the hydraulic guns and clean it to a point where it’s not sucking up blood from the prior person. Unless of course you want to sanitize it each and every time between use which makes it a total waste of your time. So it’s good old fashion needles…. Lots of good old fashion needles.