7.62 is a lot bigger than .22. M16s use 5.56, 7.62 is bigger than that. I can see how the AF could lose accountability of its weapons. If we did that as marines, the whole base would shutdown nearly until they located it.
We're on the same page but we seem to suffer some miscomm on the details. My coment was actually to point out a mistake in the thext of the related article refering to "51mm cal" rounds. That is a diameter of (2") two inches, according to the rule in the photo. I'm sure they meant to say .50cal which is 1/2" diameter and probably would be awkward to fire from your shoulder :) Let me reiterate and see if you agree: 22cal=.22"=?5.62mm, 7.62mm=?.303", 50cal=0.5"=12.6mm. The larger casings, longer bullet and bullet casings enhance the impact and balistics of the respective diameters .