We had a discussion here on brass, and its behavior after each firing.

I built a 6.5-270 Winchester.

Selected about 120 cases weighing within one grain.

This after sizing them in a 270 die, trimming, and uniforming the primer pockets.

They were sized in the 6.5-270 die, fireformed, and I started load development.

Once they were all fired once in this form, they were full length sized, trimmed, and the primer pockets uniformed again.

What surprised some here was the amount of brass being removed from the primer pockets!!

they never imagined that brass would actually flow there!!

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What surprised some here was the amount of brass being removed from the primer pockets!!

they never imagined that brass would actually flow there!!

You are saying the brass flowed to the case head and then you removed it?

F. Guffey

All my brass seems to flow AWAY from the primer pocket..... when I load them too warm.
Maybe yours is flowing the other way because you're loading too cold....NOT. LOL

That would certainly stump me to see what you discovered.

Zeke

The whole idea of sorting brass is to get brass that has the same capacity.

We have no idea of the inside, but we do have specific dimensions of the outside.

To do this we weigh them, cut them to the same exact size, and uniform the primer pockets to remove any excessive brass there.

After they have been fired, we full length size them, clean them, trim them again - some seem to grow longer more than others, some grow longer only partially around the case mouth.

We uniform the primer pockets again.

Some cases no brass is removed, some seem to have quite a bit removed.

My understanding of this is that the brass does flow, in all directions.

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My understanding of this is that the brass does flow, in all directions.

And then there are reloaders that believe they can move the shoulder back when full length sizing and there are some that are so skilled they can bump the shoulder back; and it is always "I bump the shoulder back .002" ". It is never .001" or .003" or .004" or .005"; it is always .002".

If the case gets longer how is it possible to move the shoulder back?

F. Guffey

I use a primer pocked uniforming tool to initially uniform the pockets and afterwards to clean the pockets. Even after multiple reloadings (.222 .223 .22PPC 6BR 6PPC etc) there will be some small amount of brass shavings in the residue(?).

You can move the shoulder back with your FL die, adjusting it up and down, BUT, since brass is so ductile, it springs back, and not always the same. I always laugh when I read that someone adjust their brass to the nearest .001. That means to me that they have minimum clearance between their brass and chamber. Sometimes I make chambers that will give a slight feel when you close the bolt.
Back to primer pockets; I never do anything to them.

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I always laugh when I read that someone adjust their brass to the nearest .001. That means to me that they have minimum clearance between their brass and chamber. Sometimes I make chambers that will give a slight feel when you close the bolt.

I do not laugh at, I try to laugh with. You claim you can move the shoulder back and as usual I ask "How do you do that"? I can shorten a case between the shoulder and case head, I know, it is a mind boggling thing but the shoulder I finish with is not the same shoulder I started with. The shoulder I started with became part of the neck and part of the case body became part of the shoulder.

Artifacts; that leaves me with the old shoulder and the new shoulder. A reloaders should understand when the shoulder of the case is moved back the case bulges unless the die has case body support.

And I ask; where did "bumping the shoulder back .002" come from"?

F. Guffey

Prime pocket flow seems to depend on the brand of brass. Sometimes the lot number of the same brand. I don't load anything hot! Just no need for what I shoot. I had 7 Mag brass that after 3 firings I had a hard time closing the bolt. Reamed the primer pockets, problem solved. 375 Ruger brass 10 firings no need work on the primer pockets. The last batch, same brand, two firings and hard bolt closing. I will have to ream the primer pockets next time!

instead of losing brass to primer pocket reaming, why not swage? Then maybe it will keep in it's weight class. Haven't swaged mil brass in years ever since the kids at the farm kept buying cases of .223 rem. Just a thought.