Caliber For Preppers

When preppers discuss the type of guns they prefer to stash and collect, they often cite their preference of using common calibers. This in general is a good idea, but I think that this may sell you short when you don't consider the fact that catastrophy is not a situation that will mimick situations you often find yourself in during day to day activities. This means that there is no rule of law to control or punish individuals that want to carry out their desires and means by which to survive. You will be open to unchecked levels of violence from attackers seeking your stockpile, or people that just want to come after you for what you are for your race, looks, or whatever.
Take the aftermath of Hurricane Katrina for instance. Often it was reported that there was rifle fire heard all around from rival gangs finally being clear of the threat of punishment for trying to kill each other through firefights in the streets. You may find that your area would have this issue, specifically in the inner cities.
My first recommendation to you is that you look at your situation and where you live. The reason is because alot of your stockpile is going to be based on where you are gonna be holed up. If you are gonna be in the inner cities or even in suburban areas, you may find that there is no need to prioritize on hunting calibers or high powered hunting calibers. You are more likely to be hunting rats and varmints if food becomes scarce. I would also consider that fact that you may have to shoot through barriers in your area. In this case, you may want a defense caliber that can penetrate through your surrounding barriers without deviating off course and not hitting your target with enough force to cause a critical hit. That being said, some people may be better off with a 308 rifle as a standard caliber per their local environment while others can just use a 5.56 or 9mm in a carbine to defend themselves adequately.
How about bullet design focus for your stockpile? Do you focus on hollowpoints, soft points, or just good only cheap FMJ? Well my recommendation is that you have a good variety of FMJ and Hollowpoints. I recommend you keep hollowpoints for pistols for all situations, but also FMJ for penetration and hunting if you should so need to do so when food becomes a commodity. YOu can use FMJ in defense for the most part, but some calibers may not offer the necessary termial ballistics.
Lastly, you need to consider your budget and amount. I know too many people who want to have a million rounds of ammo on hand as if they are still gonna practice and go to the range more often when society collapses. This is nothing short of a pipe dream, and more in the category of ridiculous. Realistically it is good to have as much ammo as you can get your hands on, but the question becomes how much ammo is really going to get used? Well that really depends on what you are preparing for. You may not want as much ammo if you are expecting the rule of law to be restored compared to those preparing for a total collapse with no hope of a functional government to restore order.
All in all I think this subject is important to think about before you even start looking at pulling the trigger on stockpiling, no pun intended. I am not going to judge a persons preferred event that they are preparing for, but I will recommend sound advice that can be applied universally. My main goal here is not to tell you what to do, but rather to instead encourage you to be thoughtful and open minded.