I do not know what to think of this so I will run it by you. A lot has been written abou the use of magnum primers in non-magnum cases. I was testing out a Dillion xl 650 the other day and to cross check the priming system I loaded up 6 38 special plus p nickel cases. I used older Winchester Small Pistol Mag Primers which are obviously good. These were produced about 1994-95. I loaded the primed cases into a GP 100--which is in excellant condition. No powder charge was added and no bullet was seated. I was testing the primer seating and the efficacy of the old primers. I fired off 1 primer and it fired just fiine. Cocking the revolver, I noticed a difficulty to rotate the cylinder. Fired again--just the primer and no powder and no bullet. The primer ignited fine but the cylinder was almost impossibe to turn by pulling back the hammer. Activated the cylinder release and the cylinder only came out of the cylinder gate with muscle. I retested the procedure and the same experience occured. I examined the cases to find the primer's to have cratered--making the cylinder difficult to rotate. What do you think of all of this? I looked at new factory 357 nickel cases examining the "flash hole" and I could not see any difference between the Rem 38 special nickel plus p against the 357 Rem Mag flash hole. Confused. Any thoughts? Thanks for reading the post.