I have a brand new Mark III, came with 2 mags, bought one more. They won't feed properly. When loaded with 10 rounds the spring will not bring up the next roung when fired. After about 4 or 5 rounds are manually brought up they it feeds ok. Called Ruger, they replaced the 3 magaznnes, but same problem with the 3 they sent me. Does anyone else have this problem?