Stealing weapons should be considered a next to last option in getting an arsenal together. Not only is it usually immoral, and illegal, it can also be very hazardous. Even after you have successfully stolen the guns, you have to take care that you are not caught by the authorities or the rightful owners of the guns. Military law and the laws of several states take the subject of firearm theft so seriously that deadly force is usually authorized in order to prevent a firearms theft. Some jurisdictions authorize any person to use deadly force in order to recover stolen property from a thief. In extreme situations where theft can be justified, your need must be greater than any risks involved and you should take steps to ensure that you will not be caught and punished for the theft. Obviously, those of a revolutionary type can easily justify stealing from the enemy. This is also more or less what forfeiture and confiscation laws are. Representatives of the state are authorized to steal from you whenever they think you are doing something illegal. In my book, turn about is fair play, if they steal from the individual citizens, then it is only fair that some citizens turn around and take something back. In situations where you are under some kind of hostile occupation, then theft of enemy supplies is entirely justifiable.
Usually, places where weapons are stored have a considerable amount of security. They are usually locked up tight and frequently have security systems that often include alarms, dogs, guards (even the owners) and sometimes cameras. The most frequent weak link in the security chain is evident when firearms are transported. It may be difficult to quickly open a cargo container and remove its contents, but there are many ways that you can arrange to do this at your relative leisure. For example, if you know that a certain truck is carrying the cargo that you want, it is probably as easy to steal the truck (or from the truck) as it would be any other truck. The difference is that you do not need to worry about keeping the truck if you steal the entire thing. You just need to get it to a hidden location where you can unload it quickly.
One trucker friend of mine was robbed in New York City bay a gang of thieves who opened the doors to his cargo trailer at a stoplight and proceeded to unload his truck as he drove toward his destination. They used an El Camino to carry their ill gotten gains. Every time he stopped at a light, they tossed more of his cargo to the person in the back of the El Camino. When he hit the next stoplight after realizing what was happening, he left the truck stopped and went to attack them with a baseball bat, but they were able to drive away before he could even get to the back of the truck. The thieves had found a way to unload some of his cargo without him being able to do much about it. No doubt they took the cartons home and gleefully unpacked the hundreds of valuable Taiwanese towels and bathroom rugs they had stolen. The issue was, however, that the truck was not locked any better than it was when he was carrying stereo equipment (which is what he frequently carried there) or more valuable cargo.
In these types of situations, intelligence gathering plays a very important role since it is very important to avoid wasting your efforts on stealing the wrong truck or breaking into the wrong shipping depot, ect.
A method of train looting was relayed to me a few years ago by a rather daring Chicano gangster and I think it is worthy of being told. Trains offer an interesting challenge for thieves and security personnel. If you can get somebody on to the train with some tools, they can get to the cargo and throw it overboard before the train can stop or security personnel can get to it. This is usually accomplished with the use of a 4X4 pickup and a couple of brave people (at best four but it can be done with two). Most train tracks have sections with a parallel road. What you can do is find a point in the trainís route where it will be traveling slow. The truck runs parallel to the train and the people in the bed of the truck work to get a boxcar open. Once they get it open, one person jumps and or climbs onto the train and tosses as much cargo as possible into the truck. He then jumps back into the truck when he is done. If there is a long parallel road, it may be possible to use two or three trucks, with the cargo tosser throwing or passing cargo to each truck as it pulls up, once the bed crew is finished, they pull away and the last truck picks up the person on the train. Communication and observation are critical in this type of operation. At best, there should be two people in the cab of the truck, a driver and a co-driver, and they should be constantly communicating about the road condition, obstacles and the status of the cargo transfer. If they cannot hear the people in back of the truck, then the cargo handler in the bed of the truck should have a hands-free radio to communicate with the co-driver. One of the biggest dangers (according to the gangster) is light poles and fixtures along the track. The driver must pay attention to the road and sometimes pull away from the train to avoid obstacles, this can be dangerous to the people in the bed of the truck and the person passing cargo over if it comes without warning. The driver cannot be so fixated on the cargo transfer as to not be paying attention to the road ahead. If something prevents the tossers from getting off of the train, they must be prepared to escape and evade on their own when the train slows down or stops at the train yard.