Probably a "chamber mouth" issue, though breech-face and extractor are also suspects. See this article for some solid suggestions - Tuning the M1911 for Reliability | An Official Journal Of The NRA.
Probably a "chamber mouth" issue, though breech-face and extractor are also suspects. See this article for some solid suggestions - Tuning the M1911 for Reliability | An Official Journal Of The NRA.