It appears as if my Benelli M4 Tactical shotgun has finally failed me. I have fired just north of 1,000 rounds of 00-Buck and rifled slug loads through it and she finally hung up on me. The 00-Buck loads were the wonderful Federal, law-enforcement, reduced Recoil variety with their Flight-control wad. The Rifled Slugs I was using were also the Federal L/E Reduced Recoil variety until I ran out of them and then couldn't get any more as availability dried up because of the 2008 presidential election.
I was then forced to use the Remington, one-ounce Sluggers. While they were brutal to shoot they were extremely accurate. So accurate in fact that I again secured my club's Three-gun crown for the sixth time. After a thorough cleaning it appears that the bolt rails are badly burred. It will be going back to the factory tomorrow for a full check-up. I am very surprised by this because before I bought the M4, I had a Benelli M1 Tactical and ran a slew of rounds through it without a hiccup, and the M4 is a far more robust platform than the M1. More on this when I get the patient back.
http://www.benelliusa.com/