Lapua .223 pockets too shallow

[Boilermaker]

I had the same issue with Lapua .223 brass about 8 years ago. I bought a k&m primer pocket uniformer to fix them. I now have a Benchrite uniformer from PMA as well. The K&M uniformer was to big around to fit inside Alpha primer pockets. I prefer the benchrite tool now, but they both work great.

 

[DHuffman]

Thank you everyone for your replies! They've been very helpful. I learned that 21st Century makes a micrometer uniformer, so I'll be ordering one of those. I really like that company as I've come to rely upon their mandrels for setting final neck tension. I'm looking forward to truing the pockets in this out-of-spec Lapua brass so I can do my fourth and final ladder test, finding my seating node. Thanks again everyone.

I have that uniformer as well and while it's a good tool it will not leave the side wall of the pocket unmolested.
I've got 8-10 pocket tools the PMA is the best for what you want to do.

 

[jepp2]

What do you suggest? Thanks in advance.

I have been uniforming my primer pockets for at least 15 years. All calibers, all brass. I have always used the Sinclair solid carbide mentioned by @hpshooter.

I'm not saying this holds true for your 223 Lapua brass, but I have never, NEVER, found any 223 Lapua brass that any material was cut while I was uniforming them. So I am seeing all kinds of questions floating around why yours need cut deeper. I'm not questioning you, but proceed with caution.

 

[Walt Krafft]

You need to look at the posted chart. 0.119 is not out of spec.

 

[Kracken McGraw]

Are the Lapua 223 pocket’s different from their 6BR cases?

 

[Old Navy]

This a simple RCBS adjustable and works great.

 

[243winxb]

best to deepen primer pockets

I used this

 

[Chilly807]

I've had the same problem with CCI primers in my 223 Lapua brass. Some sit slightly proud, others are flush, some are very slightly recessed.
Using an RCBS hand priming tool, if I use enough pressure to seat a proud primer flush with the case head, I may distort the rim.
Federal primers don't give me this problem.
The problem I see with removing material from the bottom of the pocket is that while CCI primers may seat better, Federal will be too deep.

 

[Thauglor]

You need to look at the posted chart. 0.119 is not out of spec.

I was going to post this too, people just don't look at data and believe what they want

 

[Webster]

Thanks! What does it attach to? Would it thread into my Lyman station or does it require a mini lathe like an RCBS case trimmer?

I have a similar tool. I cut until the tool bottoms on the case head. When the case is made the pockets are swaged in. I think this leaves a radius at the bottom of the pocket o.d. Removing this radius and maybe a little from the bottom should help. I think the primer cup o.d. rim bottoms on the pocket o.d. radius not the bottom of the pocket. Since it's a swaged pocket I would guess the bottoms of the pocket are not flat. The flash hole is also punched in, not drilled. My tool does not make the diameter of the pocket bigger.

I only have Lapua 6BR cases. The same amount of brass is not removed from every case. Each one is a little different.

 

[Rat Rifle]

You know You have a problem when You squeeze so hard Your in danger of breaking the primer tool handle, and the primer is still so proud it WON’T COME OUT OF THE SHELL HOLDER ! I suppose one could smash those primers in with a Bench Press, but I don’t think that is a good idea ???

 

[barefooter56]

I've had the same problem with CCI primers in my 223 Lapua brass. Some sit slightly proud, others are flush, some are very slightly recessed.
Using an RCBS hand priming tool, if I use enough pressure to seat a proud primer flush with the case head, I may distort the rim.
Federal primers don't give me this problem.
The problem I see with removing material from the bottom of the pocket is that while CCI primers may seat better, Federal will be too deep.

Check the DIAMETER DIFFERNCE between the FED AND CCI primers. This could be why the FED primers seat easier here.
SMALL RIFLE PRIMER POCKET DEPTH = .117 MINUMUM to .123 maximum
SMALL RIFLE PRIMER POCKET DIAMETER = .1730 MINIMUM to .1745 MAXIMUM
SMALL RIFLE PRIMER HEIGHT = .115 TO .125
SMALL RIFLE PRIMER DIAMETER = .1745 TO .1765
These are all from the SINCLAIR INTERNATIONAL PRECISION AND RELOADING HANDBOOK 10TH EDITION and are SAAMI.
You have a large diameter primer and a case with a small diameter primer pocket diameter you can have issues like mentioned above. A good priming tool that locks the priming ram in line with the cases primer pocket can help here. Especially with LAPUA BRASS.
I also use a SINCLAIR primer pocket uniformer so all primers are below flush and seated to a like depth. Hope this helps.
PS in a former life I worked at SINCLAIR INTERNATIONAL. Great job and great people. Capstone is like this also. Had the pleasure of working for BOTH Fred Sinclair and Walt Berger.

 

[nmkid]

There can be a difference in below flush and crush. A .003" crush doesn't necessarily give you .003" below flush and a .003" below flush may or may not have any crush.

You need to touch bottom regardless of your intended crush or below flush.

Winner, winner!

 

[Timon]

I shoot 223’s with Lapua brass. I use the RCBS pocket uniformed and cut the primer holes to a depth of .1230. Then I seat my CCI primers 5 thousands below flush.

 

[Chiquita]

Is the formula to measure crush?

Primer height (minus) PP depth (minus) primer seating depth below flush

i.e.
.1215 - .115 = .006
.006 - .010 = .004 << this is crush

Is this correct?

 

[Deleted member fkimble@charter.net]

The crush should not deform the primer cup, it seats the anvil into the cup putting a preload on the explosive pellet preparing it for better/more uniform ignition.

And be careful when using an adjustable depth pocket uniformer. The set screws have been know to loosen allowing the tool to just keep a going down into the pocket. For this reason I prefer fixed/one piece carbide pocket uniformers. An old cordless drill with a weak battery seems to work just fine for uniforming.

Frank

 

[Linko]

The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry about changing the depth of cut. These cutters are designed to be used every time you reload. They cut the depth of primer pockets to the correct SAAMI specification and also clean the carbon out of the primer pocket after each firing. Available in 4 sizes: Large Rifle, Small Rifle/Pistol, Large Pistol, and a PPC/BR uniformer.

SINCLAIR INTERNATIONAL SINCLAIR UNIFORMER KIT WITH SCREWDRIVER ADAPTER

Check out SINCLAIR INTERNATIONAL SINCLAIR UNIFORMER KIT WITH SCREWDRIVER ADAPTER with 12 reviews and an overall rating of 5.0, available Online at Brownells Today and many more Primer Pocket & Flash Hole products are available in our Reloading Department.

www.brownells.com

 

[Kracken McGraw]

View attachment 1631758
The Sinclair primer pocket uniformers are precision ground from one solid piece of tungsten carbide, so there is no need to worry about changing the depth of cut. These cutters are designed to be used every time you reload. They cut the depth of primer pockets to the correct SAAMI specification and also clean the carbon out of the primer pocket after each firing. Available in 4 sizes: Large Rifle, Small Rifle/Pistol, Large Pistol, and a PPC/BR uniformer.

SINCLAIR INTERNATIONAL SINCLAIR UNIFORMER KIT WITH SCREWDRIVER ADAPTER

Check out SINCLAIR INTERNATIONAL SINCLAIR UNIFORMER KIT WITH SCREWDRIVER ADAPTER with 12 reviews and an overall rating of 5.0, available Online at Brownells Today and many more Primer Pocket & Flash Hole products are available in our Reloading Department.

www.brownells.com

I just haven’t been able to make a unadjustable uniformer work on all types of brass.