Tenth firing - Primer pockets are too tight

I am trying to load 6 Dasher brass that has been fired 10 times. This is Lapua brass. I just full length sized the brass and then tried to set primers. I'm using CCI 450s. The load isn't hot and has never shown any pressure signs.

In all the times this brass has been fired, the primers went easily and my hand priming tool(s) always easily bottomed out and the primers were seated perfectly. I've always used CCI 450s.

This time, most of the primers were extremely hard to seat. They went in for the most part easily but didn't sit below flush. Then I had to adjust the primer seating depth by 5 thous and use a lot of force to seat them properly.

I'm wondering what's going on. Nothing has changed so has the brass become hard? I would have expected the primer pockets to loosen after all these firings.

 

What is the diameter of the older primers and the diameter of the new primers?

They tell you when your primer pockets get loose to try another brand of primer.

Your primer pockets didn't get smaller so the new primers must be larger in diameter.

 

Try cleaning the primer pocket with a crockagator

 

Buy an RCBS Ram Prime Unit. Works great in my single stage press.

Its possible for the rim of a 45 acp case to get larger in diameter, after many firings. Its a peening action from the case head hitting the slide face.

So maybe a 6 Dasher can get some brass flow, making the mouth of the pocket smaller? Wild guess.

I have 22 firings on some 243 brass, have not seen a pocket change. Win brass, CCI BR2

 

As mentioned, I would guess the diameters are on the chubby side by a couple of tenths, maybe .0002.
Also mentioned, clean pockets? If indeed clean,
I would call those nice people and simply state what you told us. They may be VERY interested.
The fact that you are shooting a Dasher, Lapua w 10x on them would give them an inkling that you are competent. My vote is to drop the dime.

 

Primer pockets will become more shallow and may also swell with each firing. I use a K&M primer pocket uniformer to not only clean but uniform them on each firing. Loosening of the pocket is dependent on what reamer dimension is at head but yes that the usual SOP!

 

Very interesting LC. I had not heard of that before but just added it to the mem stash.

 

So turns out this was my stupidity. I checked all the dimensions, primers, primer pockets etc. and they were all similar to the table posted above by Uncle Ed. So then I thought what else is left. So, I FL sided a case with my Harrel's die. And then checked the primer pocket depth.. it was a smaller number.
Checked the die and its primer punching stem had bent and was pushing the primer pocket out.

I feel pretty dumb right now.

 

I wouldn't!.....you worked through your problem and figured it out!...Good job!
Wayne.

 

Myself & others on AS have all made mistakes...we usually don’t post our errors. You are fine, keep asking questions. There is no such thing as a dumb question.
Ben

 

have always liked this quote

Experience is a hard teacher because she gives the test first, the lesson afterward.

As Bozo699 said, you found and corrected the problem. That is the best part and you will remember this forever.
For me, the bad part was my inability to find a way to fix the primer pocket.

 

Thanks guys. At least all my brass is not hosed. Only 80 pieces so I can live with it.

 

I would not have thunk of that for quite a while, like maybe . . . Years.

 

No, you are not dumb. The only folks in percission shooting who have not run into problems are the army of typewriter shooters. What you just did I did 2 yrs ago and I have many years of experience..... and (DUMB) mistakes. Those who do learn, those who talk....talk.

 

Don't feel bad at all! We are doing a hobby that has problems pop up ever now and then and it is kinda rewarding to find the answer you were looking for! Thanks for letting us know.

 

An expert is a man who has made all the mistakes which can be made, in a narrow field.

-Niels Bohr
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Congrats, Praveen... on taking the next step on the path to becoming an 'expert'

On a more serious note, that's how a lot of us figure things out - the hard way. All you can do is learn from those experiences, and try to help others to not make the same ones!

 

100% spot on!
Wayne