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Primer Pocket Uniforming Question

I Don’t “uniform” Lapua primer pockets.

What is the purpose of making primer pockets deeper if they are already below flush. Are you trying for a lighter firing pin strike??

I have used depth mics to measure multitudes of 220 Russian and 6BR primer pockets. They are all the same.

To me this is just another useless operation designed to fix something that is not broke.

With he Lapua 6BR, (parent case for my 30BR), and the Lapua 220 Russian, (parent case for the 6PPC), I turn the necks and fireform them. That’s it.

Benchrest Heresy.
 
I Don’t “uniform” Lapua primer pockets.

What is the purpose of making primer pockets deeper if they are already below flush. Are you trying for a lighter firing pin strike??

I have used depth mics to measure multitudes of 220 Russian and 6BR primer pockets. They are all the same.

To me this is just another useless operation designed to fix something that is not broke.

With he Lapua 6BR, (parent case for my 30BR), and the Lapua 220 Russian, (parent case for the 6PPC), I turn the necks and fireform them. That’s it.

Benchrest Heresy.
I have to agree. I ve never seen anything that makes me believe cutting primer pockets deeper inproves accuracy. I was curious as to how he was doing it because the Sinclair tool will not touch the bottom of the pocket on my brass. I was not aware of an adjustable tool.
 
Watched Jack Neary in a video with Erik Cortina as he was explaining his steps in prepping new "right out of the box" .220 Lapua brass. As far as I could tell he is saying uniforming the primer pocket is one of the first steps he takes before fire forming. Checking my new .220 Lapua brass I find the primer pocket is too deep for uniforming. The Sinclair tool will not go anywhere close to touching the bottom of the pocket. Did I miss something in that conversation ?
Does it ever touch bottom, or is it just this box of brass?

I use a K&M set up for 205 primers...... on Lapua 220 Russian brass sometimes it barely touches, and other times it takes off a considerable amount. It's a head scratcher or eye opener, and sometimes within the same box. JME. WD
 
I Don’t “uniform” Lapua primer pockets.

What is the purpose of making primer pockets deeper if they are already below flush. Are you trying for a lighter firing pin strike??

I have used depth mics to measure multitudes of 220 Russian and 6BR primer pockets. They are all the same.

To me this is just another useless operation designed to fix something that is not broke.

With he Lapua 6BR, (parent case for my 30BR), and the Lapua 220 Russian, (parent case for the 6PPC), I turn the necks and fireform them. That’s it.

Benchrest Heresy.
They aren’t the same depth after a few firings. They are moving at different rates.

Because some people do primer pockets to a depth and use a tool that is click adjustable.(0.001” or 0.0025” per click) to obtain a (+/- crush)

Some do it by feel.

No right or wrong way

I have done both ways
 
 

Looks like it’s good for PPC, BR and 47
I use this tool from PMA. It will cut any small rifle primer pocket to .124. I use it for my 6BR, 6.5x47L and .223.
I like to uniform the pockets, so I get a consistent primer seating depth. I don't shoot well enough to know if it makes a difference. It's a one-time operation like neck turning. I just like doing it.
PopCharlie
 
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Does it ever touch bottom, or is it just this box of brass?

I use a K&M set up for 205 primers...... on Lapua 220 Russian brass sometimes it barely touches, and other times it takes off a considerable amount. It's a head scratcher or eye opener, and sometimes within the same box. JME. WD
Tried it on 3 different boxes and it has not touched on either.
 
I've used the Sinclair tools, for both large and small rifle primer pockets for many years now. In some case lots, the tool will not cut the bottom of the pocket, the pocket, as manufactured is too deep for the tool to reach.

Like everyone else, I'm always looking for an edge in accuracy. I started several years ago using these tools. Perhaps it makes a difference in the ultra-precision game of benchrest or long-range shooting, but after shooting several thousands of rounds with pockets uniformed, I can see no difference on paper at least to the level of precision I'm shooting at, i.e., 1/2 moa range.

The main advantage I observed is that it is much easier to clean the primer pockes after it is uniformed if the tool will reach the bottom of the primer pocket. If not, it still does a fair job of removing excess primer residue.

For a precision hunter, I would be reluctant to use an adjustable uniformer for concern of cutting the pocket too deep thus creating a reliability problem especially when I have seen no performance benefit to uniforming the pockets.

Is there test data that shows an advantage? If so please post or list reference. I would like to view it. Thanks.
 
when Sinclair was Sinclair.. they had a primer pocket uniformer just for Lapua brass.. which went deeper.. i have one of them, don't know if they still have that under the Brownell's banner or not
Back in the day when I lived in Wyoming before computers and the Internet took over the world I used to leaf through my Sinclair catalog until the pages started falling off.
 
Back in the day when I lived in Wyoming before computers and the Internet took over the world I used to leaf through my Sinclair catalog until the pages started falling off.
I have several old Sinclair catalogs, but I also have several that I downloaded years ago from their website..... those pages don't wear or fall off.
 

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