Thread: Factory loads exceeding reload speeds with less pressure signs

Grandpamac basically suggested what I was going to say - light load with a case resized past what's needed can create this issue. What happens is the firing pin slaps the case forward and the pressure generated by the powder doesn't shove the case back. Something has to give, and in this case it's likely the primer shifting backwards.

As noted - the load is quite light per the current recommendations as well although in the past the loads have been lower so it's not in itself a safety concern and I would think that there are a number of issues that are contributing.

As far as setting up the full length die - I would suggest firstly checking a factory load case fired in that rifle and making sure it chambers again. Then mark the neck and shoulder up with vivid marker pen and wait for it to dry, after the cleaning and brush the neck out and a bit of lube inside obviously. Set up your shellholder in the press, move it all the way up without the case in and with the ram fully up wind the die down until it contacts the shellholder. Then back it off one turn, and lock it into place. Retract the ram, chuck the marked case in and send it up and see where the marker pen has been scraped off the neck. That will tell you how far down the case the die is going, you basically want it just short of the shoulder and if you get stiff closing of the bolt on reloaded rounds just adjust the die a little further down. Somewhere on here is a picture showing how many thous approximately is 1/8 turn on a standard die, I think it was 10 thou (0.1mm is about 40thou for our purposes thats close enough anyway).