Brass sizing & trimming question

[Calplinker]

I've been sizing and trimming .308 brass today using the electric trimmer attachment on my Dillon 550b. This is my first time doing it.

Got it set up and for 90% of the cases, they come out perfect as judged by a sizing gauge. Most of the brass is commercial of mixed types with some being military. About 1/3 of the used military brass won't seat fully in the sizing gauge after being run, so I'm setting it aside. A very small percentage of the commercial brass does the same thing, but only like 5% or so. This small pile of 50 or so isn't off by much, but it is definitely too high and won't seat.

What do you folks do with this brass? My inclination is to finish sizing and trimming all the cases I have, then try to reset the die depth and try again on those that I've set aside.

The downside to this, is of course having to reset everything.

Is this common? Do you folks do this, or just not use the brass that won't size properly alongside everything else? It looks fine. No bulges or splits, etc.

I did notice that 100% of my once fired Hornady, Federal and Priv match grade brass all went through and came out perfect. No cast offs. Same thing with some 2X fired Winchester.

Do you guys seperate by head stamp and change settings for each one as necessary?

[ocabj]

Where this brass come from? When I resize rifle brass where it's unknown as to what the brass came out of (what gun), I always use a small base resizing die that's turned down at least a half turn past cam on the top end of the press ram to ensure it will fit any chamber.

After that, when the brass is used in my own guns, I know that I can use more lenient sizing techniques (e.g. bump sizing).

[Calplinker]

Brass is from two sources. About 2/3 of it is mine and was factory new an fired in my .308 AR, M1A, with the match stuff fired in my .308 bolt gun. The other 1/3 came from the guy I bought the press from. Most of that is once fired Winchester he picked up from a range meet he participated in. Total for both is about 1500 cases or so.

[Calplinker]

The military stuff is all mine and was fired in either the M1A or .308 AR.

[ocabj]

Interesting. I'm curious as to where on the case the brass shot out of the M1A or AR is over spec even after resizing. Could be really loose in the body closer to the head/rim.

[Calplinker]

Judging by how it seats in the sizing gauge, the neck needs to come down a few thousands. The trimmer still peels off a bit of brass at the neck. Looking at both sides of the gauge, my guess is once the due is turned down a half turn it do, it will seat fine. I'd need to raise the cutter motor by a like amount.

Is this common? I've never reloaded and have very
Limited knowledge.

I do have a bag of 500 or so .308 brass cases the seller gave me that he labeled as trimmed and sized. They are absolutely perfect in the sizing gauge and are also all mixed brass. He never separated by brass type but they were all shot from his guns. I don't know what type of guns they were.

[Munk]

Is your sizer a FL sizer? Is it fully down against your shellplate when sizing?