Howdy Rainbow4758,
Very interesting question you pose. I'm going to guess when you say 'Bug out- survial Bag' that you live someplace city/ suburban that you would need to leave from. With usage from impending obstacles to get to your destination, then the use of said knife at that destination for the above mentioned tasks. The KA BAR lineup has many excellent knives that would suit your purpose. My favorite to start would be the BK2. At 1/4 inch thick and 5.25 inch long, there is nothing that this bad boy can't pry or baton through. It's been proven;
http://www.bladeforums.com/forums/showthread.php/839944-BK2-test-the-final-part-%28LOTS-of-pictures%29. The only disadvantages you would find with this knife is the weight (I don't personally find it too heavy), and the blade length (most folks wish for longer).
Next I would recommend a BK3.
[video=youtube;QSuZxLT8_iY]https://www.youtube.com/watch?v=QSuZxLT8_iY[/video]
If it can dismantle a car :thumbup: There is also a Gentleman on here who goes by 'DOC CANADA' who frequents BK3 use outdoors (forgive me I can't find the reviews to link).
BK9 / BK7/ BK4 would fall into my next set of recommendations. They have the length that the 2 doesn't have, and will serve you well for all above tasks.
The 15 / 16 / 17 will also do a fair job as a survival style knife, just not 'as well' as the full handled Beckers. One of the moderators here has used his BK16 for the R.A.T course.
I would also implore you to consider some of the KA BAR line as well. The standard #1217/18/19/20 or with the kraton G handled #5011. This knife design has been used by the military now for over 70 years and hasn't changed (that's got to say something!).
If it has a KA BAR stamp on it, and its made in the USA you can't go wrong. Good luck with your hard decision :thumbup:
If there is a place local that has them, I would really suggest feeling them in the hand first
