I have a cousin who lives in Illinois and joined the Marines. He's 20 now. He can shoot fully automatic weapons in the military and has won awards for handgun precision and skill.
But he can't buy a handgun in his home state or drink a beer.
Make it make sense.
It’s my understanding, for the most part, that they do not have constant access to fire arms, that they are somewhat tightly controlled on base precisely because the army has learn widespread indiscriminate access is a safety problem despite all this training.