I have put a lot of thought into what kind of ammo to stock up on. In my opinion, the 22 long rifle cartridge is the best caliber to have for a few reasons. I know that in saying this I am going to spark the wrath and fury of naysayers who are stuck on larger caliber ammo. For a bug in strategy, where space and weight are of no concern, then I agree that the bigger, the better. However, when you are carrying your entire ammo supply on your back, weight matters.
I believe for a bug out bag you need at least 1,000 rounds of ammunition, although you will never have enough, but we must be realistic. For 1,000 round of 45 ACP you will be dragging around 46 lbs, while 1,000 rounds of 22 LR will only weigh around 7 lbs. For the 45 ACP this is a huge problem. A 50lb pack is very heavy. It is about the maximum weight one can carry without being too uncomfortable. So unless your bug out solution is to only bring ammo, I strongly suggest 22 LR. Below is a weight chart of some of the more popular rounds.
22LR 36gr 100rds = 0.70 lbs
22WMR 40gr 100rds= 0.90 lbs
9mm 115gr 100rds= 2.55 lbs
40 snw 180gr 100rds= 3.63 lbs
45 ACP 185gr 100rds= 4.05 lbs
45ACP 230gr 100rds= 4.62 lbs
38spl 130gr 100rds= 2.93 lbs
357mag 125gr 100rds= 3.08 lbs
44mag 250gr 100rds= 5.55 lbs
5.56mm 55gr 100rds= 2.51 lbs
7.62×39 122gr 100rds= 3.61 lbs
7.62×51 146gr 100rds= 5.43 lbs
20ga #3 buck 100rds= 8.77 lbs
12ga 00 buck 100rds= 9.59 lbs
When you are in a bug out situation, you will be relying on small game as a food supply. I have personally never shot a squirrel or rabbit with a 45 or a 308, but I can only imagine that you would have little left for food when the damage is done. Smaller bullets mean more food.
Now I know what is on everyone’s mind–gangs of starving people doing whatever it takes to survive. The 22 is known for its lack of stopping power. We would like to think that even in a disaster situation that human beings will respect each other, but history has shown us this is not true. Just look on Youtube at how people behave during Christmas to get their kids the right toys. Imagine how people will behave when you have food and their children are starving to death. People will do whatever it takes to survive and as a prepper, you will be public enemy number one. A lifetime supply of food will not get you very far when your neighbor breaks into your house with a gun and wants what you have because his family is starving. Maybe you have enough to share with one neighbor and his family, but what about your whole neighborhood? A year’s worth of food won’t last a day for 500 people. Therefore, I want to stress that it is important to have a gun with more stopping power, 380 and up should do the trick. If you are bugging out, you will probably not encounter too many people in the wild on a daily basis, and those you will encounter will probably have survival skills and gear of their own. Only an idiot would bug out to a remote location lacking proper survival skills. The average American would not make it a month fending for themselves in the wild. There is, however, the journey out of town. There will likely be roadblocks setup by people whose sole purpose is to take what is yours. An even worse scenario is if there is a fuel shortage or EMP that wipes out the electrical circuits of motor vehicles and you are forced to walk out of town. Even if you leave at the first sign of danger, the world will already be in a state of chaos and your bug out bag is no more than an advertisement for supplies, food and water.
They say a 22 is better than nothing. A rock is better than nothing as well. However, a 22 can be deadly. A 22 in the heart will kill just as quickly as a 45 in the heart. A limb shot will not kill with either, unless you hit a major artery. My theory is, if someone is attacking you for your supplies, they are doing it to survive. If you point a gun at them, weather it is a 50 cal or a 22, their best chance of survival is to back away. They will more than likely recognize this. If they do not, a 22 round in the chest should wake them up, or put them to sleep. Either works. Also, keep in mind that for the weight of every 45 bullet you carry, you can carry 6-7 22 shells. One might do the trick, but 6 shots in the chest will more than likely hit something vital, so as far as weight is concerned, I believe the 22 wins out again in killing power.
Most preppers live normal lives. We do not have hundreds of thousands of dollars to spend on guns and ammo. Everything for the 22 is cheap. The guns are generally cheap, the ammo is cheap, and the accessories are cheap and they are all so common that you will likely be able to acquire them even after the apocalypse. At my local Academy, I can purchase over 500 rounds of decent 22 LR for about $12. For 45 ACP, I can purchase 50 rounds of decent FMJ for around $21. It is around $20 for 20 rounds of decent JHP. This means for about $24 dollars I can stock my bug out bag with over 1,000 rounds of 22 LR, while it would cost around $420 to stock 1,000 rounds of 45 ACP FMJ and around $1,000 to stock 1,000 rounds of 45 ACP JHP.
Another benefit is that 22 LR works for both pistols and rifles. While there are a few pistol caliber rifles and vice versa (I am seriously considering the Beretta CX4 Storm Carbine in 45 ACP), you will still suffer all the problems mentioned above. I have a lot of rifles and pistols in many different calibers. I wish I could stock for them all, and maybe one day I will, but for now I must choose the ones I think will serve me best. My 22 LR handguns and rifles are accurate, light, versatile, and effective. I can stock up on one caliber and use it in my rifle and my pistol.
In summation, I will still carry my 1911 when bugging out and have a decent supply of ammo for it. However, the bulk of my ammo will be 22 LR. If you are planning on bugging in and you have plenty of money and space, then by all means, stock up on the largest things you have. Also, do not forget to prep your bug out location. Store most of your ammo, food, and supplies there. Your bug out bag is just to get you there and 22 LR is your best companion for the journey.