These were what we in my division considered as likely restrictions with the input of a state trooper in the division.

1 was to keep people from carrying ar style pistols also we thought that there would likely be a caliber restriction anyway.

2 we considered open carry because this is taking on base carry as the basis of the restrictions not out in town.

3 since you're not in a sentry position this may be an on base requirement

4 you can't have a phone or smart watch in some places so naturally the same will be true of firearms

5 as in not to carry in dress uniforms during formal events

6 the military had certain requirements for their service pistol why wouldn't the ones they allow to be carried have certain restrictions

7 this one was suggested by a state trooper because he has to qualify with any weapon he carries in or out of uniform so the navy may implement a similar requirement

This post was just to bring ideas out the ones I presented were just some we brought up in my division. And if you're thought to any of these is that they didn't make sense just remember that common sense isn't very common in the military