A bag SUCKS.

What you want is a BACKPACK. Keep your hands free to carry other things; like protection, or so you can actually pick stuff up and the like while traveling.
A 2 day pack size bag. (WalMart, $30.) The right one will even have loops on it that can hold a rifle on the pack, barrel down in a loop and the butt strapped up in the air.
Nylon; as light as you can find. While I like rigid frame packs, I suggest a semi-rigid unit because they are more comfortable for people who do not pack all the time.

Pack light. As in..... you best load it up and it should weigh no more than 30lb for the average person. Any more, and you will not be able to ruck with it for very long. YES, this includes the water weight and ammo.

30lb is a lot more weight than you think it is when you carry it for 4hrs of non-stop walking. A LOT more.

Best plan (Plans always get sidetracked and ruined....) is to PLAN with a friend or family member who is relatively close by, and figure a way to hike to their place, or them to hike to yours in case of an emergency. You are not really 'Bugging out.' You are 'Bugging in' at your buddy's place.
Say your place is vulnerable to hurricane/ flood. You set up with a friend whose place is not too many miles away where they are more secure from hurricane weather. Tornados, same theory. (Yes, I KNOW a hurricane can wipe out everything for 10 miles in every direction. But with 2 houses 10 miles apart??? One of them is going to survive to a decent degree and be habitable.)

Plan to store some basics; canned goods, propane, water, food procurement devices (Fishing gear/ hunting gear) And some real basic stuff.
While it might take me 2 days to get there, I have a simple group of 4 houses and it's about no more than 15 miles from one to the other. If things got nasty and I had to leave, there are some simple options. Also, they very well might come my way for some shelter and food. I hope it doesn't happen, but all it takes is one real good fire or earthquake, and all bets are off in Ca.

I am directly down wind from Chicago and less than a mile away from an interstate 69 exit heading south from Detroit. If the fallout doesn't get me the thugs heading south would. Considered taking a canoe with a folding bicycle with me in my car. We have rivers heading south also. I have family within 3 hrs south. Not sure if that would be far enough but it is a start. Saw the movie " The Road". Depressing as all get out. Dirty bombs or Yellowstone going up would be a bear.

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CA ban no sharp pencils ovr 3"

Shoot, a fella could have a mighty fine time in Las Vegas with that!

I have an everyday carry bag to get home. I believe in staying put.