I highly recommend this rifle
Kel-Tec : SU-16A, SU-16B, SU-16C, SU-16CA, SU-16D, SU-22
Light, Folds, Fits in a backpack, Accepts standard M-4/M16 magazines, Threaded barrel, Low cost
Gen Info: This Rifle is available in six different models. The stocks are interchangeable (Example) you can take the stock from the SU-16C and put it on the SU-16A. Just remember, this might affect your state laws. The Alpha and Bravo are legal in almost every state when fitted with 10 round magazines yet cannot fire when folded. The C, CA, and 22 Models have threaded barrels, thus restricted in some states. The C, CA, and D model will fire when folded. The D is for law enforcement or if you have the ability and $ for a license. All but the 22 are made for 5.56 and .223, some older models might be .223 only.
NOTE: The Kel-Tec SUB-2000 is another great backpack survival rifle. Different versions of the SUB-2000 will accept most modern handgun magazines.
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