I've always been of the opinion that you should carry as much spare ammo as is practicle!! Personally, I carry no less than 25 rounds, both in the gun and as spares. This is why!!! http://ap.google.com/article/ALeqM5jYndpW6cS3ZgCtGkwPyH26d_N3CAD90KDLK03 Even the little gangpunks in my old neighborHOOD traveled in groups of not less than five!!