Just ran across this thread looking for info on S&W turnaround times. I had to send my brand new OR model in for the EXACT problem two weeks ago. I am familiar with the platform, and mine seemed to have the problem with more than 10 rounds in the magazine. I believe deeply that my bolt was coming forward before the magazine could push up the next round. If I spec'd and built the rifle then I would add buffers, etc, but I feel a rifle from the factory should have ZERO malfunctions, so it went back to the the folks who built her. Just hope to get her back soon in full working order. Then I can add my Spikes buffer, and BCM charging handle.