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Reaming primer pockets

Never had to do this before. But got some Starline brass that CCI 450 won't seat all the way into.... leaves the primer protruding out past the case base . (Seats fine in Nosler brass.)

I took a hand reamer and modded the pocket so primers would seat flush to case base.

What am I missing here / doing wrong?

Thx.
 
I normally use a K&M uniformer on all my brass, but it's a pain when you HAVE TO on new brass.

I load for a 17 Hornet, and the only brass maker is Hornady, and their primer pockets also had to be uniformed to prime the brass. Those cases are really small and hard to hold while using the uniformer, a real chore to get them all prepped.

If the Starline is not made to spec, then I'd definitely contact them.
 
Never had to do this before. But got some Starline brass that CCI 450 won't seat all the way into.... leaves the primer protruding out past the case base . (Seats fine in Nosler brass.)

I took a hand reamer and modded the pocket so primers would seat flush to case base.

What am I missing here / doing wrong?

Thx.
You don't know what's actually going on unless you're measuring both the primer pockets and the primers. Otherwise, you're just guessing.

Your Starline brass could indeed have pockets that are way shallower that your Nosler brass and making then deeper is just fine, especially if you can't get them seated below flush with the case base. Just be sure you're getting enough "crush" to seat the primers so that the primer's anvil is properly sensitized for good consistent ignition.
 
Using the depth guage on this Starline brass, I came up with three rough groups of pocket depth, on 1-2x fired brass....

1 - 0.095"
2 - 0.112"
3 - 0.118"

Never had primer seating problems before, but I guess I wasn't paying attention.

Checked the new Starline I had.... varied from 0.119 - 0.128

Best as I can remember it was 2 different batches.

QUESTION: Ever had pocket size change with firing?

I will be sure to check in the future.

Is there a "Go - NoGo" gauge for primer pocket depth? Or maybe I just get a uniformer and "true up" all my pockets all the time. That seems ridiculous for new better quality brass.
 
QUESTION: Ever had pocket size change with firing?
Yes, they do but not a whole lot.

Is there a "Go - NoGo" gauge for primer pocket depth?
The 0.117" limit on the specs above is a good way to roll, and if you don't own a fancy primer pocket depth gage you can do just fine with the tail stock of your caliper.

If you want a very good gage you will get many different views in short order, but I will give an example as the Accuracy One gage. There are others.

1703123184280.png
 
Using the depth guage on this Starline brass, I came up with three rough groups of pocket depth, on 1-2x fired brass....

1 - 0.095"
2 - 0.112"
3 - 0.118"

Never had primer seating problems before, but I guess I wasn't paying attention.

Checked the new Starline I had.... varied from 0.119 - 0.128

Best as I can remember it was 2 different batches.

QUESTION: Ever had pocket size change with firing?

I will be sure to check in the future.

Is there a "Go - NoGo" gauge for primer pocket depth? Or maybe I just get a uniformer and "true up" all my pockets all the time. That seems ridiculous for new better quality brass.
Yes, my primer pocket depths change with firing. It's always obvious to me when I clean my primer pockets that I've uniformed where I get a very tiny and small amount of brass shavings mixed in the the carbon being removed with the uniformizing tool I use for this operation. It's a VERY small amount. And yeah, this is simply "truing up" the primer pockets when I clean them.

The tool I use to measure my primer pockets and seating depth is that one RegionRat has shown above. It makes fast work for taking those measurements. I especially use it any time I get a new batch of brass or a different brand of brass so that I can know where I need to set my seating tool to get a consistent amount of anvil crush I'm after.

Here's some Frederal .308 brass from a couple years ago that I was using that shows an unsual amount of movement in the base of the primer pocket (hot loads):

1703127893035.jpeg
 
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My untouched Starline brass has this weird elevated center area in the primer pocket. Is this normal to have the center raised like this? My Fed and Lapua brass is all flat.
 

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No new brass has a flat bottom, the "corners" are rounded. I use a uniformer on new brass, it cuts the edge first, then each time I reload I use the same tool to clean the crud out down to bare brass. They stay flat and the same depth. Sometimes the center around the flash hole is high enough to get cut a little too. All it takes is run your finger over the brass base to feel if the primer is flush or just below.
 
Using the depth guage on this Starline brass, I came up with three rough groups of pocket depth, on 1-2x fired brass....

1 - 0.095"
2 - 0.112"
3 - 0.118"

Never had primer seating problems before, but I guess I wasn't paying attention.

Checked the new Starline I had.... varied from 0.119 - 0.128

Best as I can remember it was 2 different batches.

QUESTION: Ever had pocket size change with firing?

I will be sure to check in the future.

Is there a "Go - NoGo" gauge for primer pocket depth? Or maybe I just get a uniformer and "true up" all my pockets all the time. That seems ridiculous for new better quality brass.
Get Real,

I use this set of tools: Primer Pocket Gauges

HTH,
DocBII
 
I think mine looked somewhat like that. Figured I would wait till everything moved a little till after first firing, then hit the pocket with the uniformer.
Here is what Starline said:

That is normal for anything we make that has a double heading process like 5.56,223, 300 Blk, and 300 Ham’r.
 

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