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uniforming tight Alpha primer pockets

TackDriv3r

I have a large lot of 6 Dasher Alpha brass, all are 1 X fired. Noticed primer pockets are too tight to use with standard small rifle pocket uniformers so I bought a Sinclair 6 Dasher pocket uniformer. The pockets on the Alpha brass is tight, just done 50 pieces and its a pita. It does shave about .003" off the bottom when it bottoms out. Is it worth it to uniform the pockets? I don't recall pockets being that tight on my 6 BR Lapua brass. I like to keep my pockets clean after each firing. Measured pocket depth after uniform and its .122"

Weird that after priming, my depth on a loaded primer varies from .004-.006", does this indicate a bad priming tool? I have the original old RCBS hand priming tool that I had for 25 plus years. Is it time for a new hand priming tool and which brand is good?
 
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When I first tried the new Alpha PPC brass, I very quickly realized some of the same concerns you've listed. So before I went any further, I gave them a call to ask them about the tight pockets, and how to clean the pockets, etc. Glad that I did and would recommend you do the same to get your info straight from the manufacturer.

As far as a worn priming tool, it's possible after that long it may have worn a bit. I use the 21st Century hand tool and am very happy with it. Good luck and hope it works out well for you. JME. WD
 
Rim thickness causes your variance. When pockets are that tight seating by feel is more difficult. The thought is the need to uniform. Alpha will claim their OCD stepped pocket is designed tight. When the primer is pushed into the pocket the case is raised into the shell holder. Shell holders have to have slop to allow case to fit. If the rims aren't cut identical, there is your variance.
Rims are not controlled like that..003 crush will keep them seated.
 
WyleWD said:
When I first tried the new Alpha PPC brass, I very quickly realized some of the same concerns you've listed. So before I went any further, I gave them a call to ask them about the tight pockets, and how to clean the pockets, etc. Glad that I did and would recommend you do the same to get your info straight from the manufacturer.

As far as a worn priming tool, it's possible after that long it may have worn a bit. I use the 21st Century hand tool and am very happy with it. Good luck and hope it works out well for you. JME. WD
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Definitely treat yourself to the 21st Century priming tool..! Love mine and click adjustable to .001” @ click for perfect depth control and plenty of leverage on the all stainless steel tool.
 
Yikes!!!
I would not be messing with any primer pockets on that fine Alpha brass.
Yes , it’s time for a new hand primer tool.
Get a 21st century hand primer tool and just set the primer to the bottom plus a little crush.
No need to fix what isn’t broken….
 
TackDriv3r said:
I have a large lot of 6 Dasher Alpha brass, all are 1 X fired. Noticed primer pockets are too tight to use with standard small rifle pocket uniformers so I bought a Sinclair 6 Dasher pocket uniformer. The pockets on the Alpha brass is tight, just done 50 pieces and its a pita. It does shave about .003" off the bottom when it bottoms out. Is it worth it to uniform the pockets? I don't recall pockets being that tight on my 6 BR Lapua brass. I like to keep my pockets clean after each firing. Measured pocket depth after uniform and its .122"

Weird that after priming, my depth on a loaded primer varies from .004-.006", does this indicate a bad priming tool? I have the original old RCBS hand priming tool that I had for 25 plus years. Is it time for a new hand priming tool and which brand is good?
Click to expand...
Yeah, the pockets on the Alpha brass have a slightly smaller ID than Lapua brass, making is, as you say, a PITA using an RCBS priming tool. I also have an RCBS primer pocket uniformer tool, but I don't use it on my Alpha brass because of tightness. I also have a 21st Century pocket uniformer and its OD is a couple thousandths of an inch less than the RCBS's making it much easier to uniform my Alpha brass. I still use my RCBS tool for my other brass with pockets that aren't so tight.

:eek: And yeah, after 25+ years . . . it's probably a good idea to get another RCBS uniformer even since the carbide one doesn't really costs all that much. :rolleyes: :)

Differences of .004 - .006 for primer seating depth could be just because of differences in the height of the primers due to where the anvils are??? And depending on the type of tool used to seat them. I'd say, in most cases that amount of variation isn't going to make much difference in your ignition as long as you're at the bottom of the pockets and nothing above flush.
 
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My experience with Alpha ocd dasher brass, various lots, is as follows:
Out of the box the primer pocket is .112 deep. With PMATOOL uniformer goes up to .121
I use CCI 450 ( usually .119-.120 thick) and seat them .2 or .3 below flush. All measured with the Primer Precision Gauge. Using the xxics primer seater last version.
Not missing a beat with all my actions ( soft 70N springs, Zermatt TL3 or ARC CDG ) for the entire match season so far ( approx 2k rounds)
When I was not prepping my pocket I had randomly ignition faults ( 1 over 50 rounds) I suspect due to excessive primer crunching.
 
I do absolutely nothing to primer pockets. Never have.
I like the idea that the Alpha 6PPC brass has a primer pocket just deep enough so a Federal 205 is only about .002 below flush.

I made a little tool to clean the carbon out of the pocket after each firing, as the Sinclair tool I have had for over 25 years is too tight.
 
Alpha definitely has tighter primer pockets. I open mine up with the Sinclair uniformer after the first firing. That has worked well for me. I have over 15 firings on some and still no signs of loose primers even after running in the uniformer. I’d say they are still as tight as new Lapua. It is a PITA the first time the uniformer is used. After the first time it’s business as usual. If you decide to do this get a case holder. I made one out of a barrel stub using a chamber reamer. Several folks sell them as well.
 
LVLAaron said:
Don't monkey with the Alpha pockets. Alpha lasts forever and it's because the pockets are tight. Leave them alone.
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System just won’t let me give 2 Thumbs Up… But here you go…
I have followed this and wondered why anyone would want to enlarge the primer pockets as personally I consider that a tight pocket is a +
The almost universal failure on cases is the primer pockets rather than anything else.
I would think that starting out tight would extend the life of the case.
Same applies to White River primers as they too seem to run just a tad tight in the pocket but that is a good thing for those of us who may have primer pockets loosening up…
 
Fire Dog said:
System just won’t let me give 2 Thumbs Up… But here you go…
I have followed this and wondered why anyone would want to enlarge the primer pockets as personally I consider that a tight pocket is a +
The almost universal failure on cases is the primer pockets rather than anything else.
I would think that starting out tight would extend the life of the case.
Same applies to White River primers as they too seem to run just a tad tight in the pocket but that is a good thing for those of us who may have primer pockets loosening up…
Click to expand...
I deepen mine because my primers are a few thou proud. I use the k&m tool which removes very little from the sides but deepens enough to get the primer 5 thou below base
 
SeabeeKen said:
I deepen mine because my primers are a few thou proud. I use the k&m tool which removes very little from the sides but deepens enough to get the primer 5 thou below base
Click to expand...

That "very little" is what makes alpha alpha - What primers are you using?
 
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