Hi every one, before i ask my question i want to thank all of you who have giving me ideas and very helpful aswers. Thank you all. Ok i have an mp15-22 rifle as you know is in .22lr. Now, this rifle is being very reliable to me, it never fails with cci mini mags and cci stingers, so do you think that i could use this rifle as a self defence weapon? Or you think is not powerful enough. If you say "yes" then could you tell me which kind of ammo ( brand) should i use in order to defend my house? Thanks again any answer will be very helpful to me.