.22's are great. Ammo is cheap, light and abundant.

Another BOB type compact rifle is the KelTec line of rifles. They make them in .22, 9mm, .40, and .223. Here is a pic of the sub-2000. It folds to 16x7, so it would fit nicely in a backpack, and weighs only 4 lbs. It uses Glock magazines.

The polymer sights concern me a bit as far as durability goes... but for an 'emergency/BOB' type gun it may fit the bill.




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