[JT Hatter]

His AR-15 jammed. Didn’t the fellow who shot up the movie theater in Colorado have an AR-15 that jammed? Is this a problem with the rifle?

And God bless the poor victims of these crazy people.

[Domangart]

Only two things could happen, A double feed caused by one or both of the top lips of the mag have been bent. The other relates to a carbon build up inside the bolt and ring alignments.

[smokingfrog]

It’s not a problem. The CO shooter did use a 100 rnd mag, which can have feeding problems, depending on the quality of manufacture. It is best to avoid using soft point bullets, however.

[jim_trent]

> an AR-15 that jammed? Is this a problem with the rifle?

I noticed the same thing. My experience has been that most magazine fed semi-autos work better with one or two rounds less than what they claim (say 13 rounds in a 14 round magazine or 28 rounds in a 30 round magazine). My bet is that they loaded them up fully (and maybe even one or two rounds extra) without trying them for function.