Unburned powder left in case

[wtkaiser]

I had the same symptoms, but I was loading for 7mm Mag, and maggie primers proved vital with that round and that gun, as you might expect. Do the firing pin strikes appear normal?

[mark501w]

stop shooting pull bullets! Some of the ball powders like mag primers, some of the slow powders act funny under reduced loads. It's all dangerous.

[dhagerty]

ball powders are harder to ignite than granular powders. overall, you should use a magnum primer with ball powders.

let us know if he finds the problem.