Originally Posted by CRNA
I am just learning specifics of reloading, but form what I have learned, it sounds like the gas is escaping around the neck (which I think is normal). The problem is the gas shouldn't make it down to the shoulder because the shoulder should expand and seal off those gases inside the chamber at the time of detonation. That may not be a whole lot of help only to say that my 7mag doesn't get the gas all the way down the shoulder. Good luck.
I think the neck should be free from fouling, too (It is also intended to form a seal with the chamber) though I think it is less surprising if/when it shows some powder residue. I believe the shoulder sees pressure before the neck does (and for a longer duration), so it has a better opportunity to expand and form the seal.
The more I think about all this, the more I'm inclined to think this is happening because the brass I've been reloading has been worked too much in each cycle (using FL dies which were pushing the shoulder back 0.008") and the powder in my latest recipe develops lower pressure than maximum.
I would like to try annealing some of the case necks, and repeating the recipe, though I've never done any annealing. It looks like something that can add more variation if you don't do it right, and I don't really have $325 to spend right now on a nice annealing system.
So, maybe I'll just buy some new brass, and start neck sizing only (and get my FL dies set up to do just a "minimum shoulder bump" . . . of about 0.001 or 0.002")
Anybody have an opinion on Norma brass?
I've been using Nosler, and would like to stick to the same brand . . . but everybody seems to be out of it at the moment. I found one place which seems to have Norma, though . . . and it seems to be about the same quality as the Nosler, maybe even a little better.