Case dent problem

[greenmountainboy]

Had a strange thing happen today while working up a load, I think I know the answer, but I thought I'd ask to see if there is another possibility. After firing a fouler, my first shot with a light load went normally, until I pulled the brass out. There were four dents just below the shoulder of various sizes. You can see them in the attached photo. I tend to leave the bore wet with oil, and usually do not run a dry patch through before shooting, so I think it's just from a buildup of oil. Any other more likely answer? Thanks for the input.

Justin

 

[billmo]

I believe you are right. It don't take much to dent a case under pressure. Bill

 

[Cheechako]

. . .my first shot with a light load. . . Justin

Justin

I think you answered your own question. Many times, a light load will not expand the neck enough to seal the chamber and gas will bleed back along the sides of the case, denting them from the outside, just as your photo shows.

Ray