Thread: AR-15 Problems

hey guys on my AR-15 I have a 5 round mag been told that 5 can be to much only put 4 rounds in.. But here is my problem when I put the mag in pull back on the charging handle and the bolt comes right open locks into place, I push the release button to close the bolt. It wont move at all to pick up the first round.. its like it jams or is stuck.

other problem some times the bolt wont stay open at all after pulling the charging handle it will close, but when it does this it might pick up the first round but only close 95% of the bolt..

Im using .223 55g been reading some say this is ok others say 5.56 use .223 62g ammo

Thanks guys sorry if dumb question..