I learned that on a thread on this site many months ago. and yup, mine does the same thing. I still shock non AR people when i show them this, ( this includes new LEO's too). I had a short conversation on this board about the same time that he had an AD while on a call. chambering a round on his patrol rife. he was saying luckly his SGT was standing beside him when it happened and saw what he did, (everything right) including pointing the muzzle to the ground when letting go of the charging handle. blew a chunk of asphalt to heck, no injuries.
he advised me to ride the CH down and use the Foward assist to seat the round if i ever needed to chamber one in the field. I learned from HIS lesson.. whoever it was , THANK YOU. and i tell everyone i know that handles AR's about this "AR-ism".