The availability of cheap ammo was a serious consideration
I worked for the phone company for 40 years and in the 80s we had a call to do some work on a guy's house in Petaluma. He was a retired Air Force guy. He wouldn't let us under the house but finally said it was OK. The whole crawl space was packed with cases of carbine ammo. thousands of rounds, hundreds of thousands of rounds. He was taking a few home every week. I should have extorted a few cases from him but I was too honest. Imagine how much of that stuff was out in the 50-60's? My friends in the NG were doing the same thing with M1 clipped AP under orders to take it home. SL 53 fabulous ammunition by the case.