Results 1 to 8 of 8

Thread: How Much Brass Removed When Uniforming A Primer Pocket?

  1. #1
    Member
    Join Date
    Jan 2007
    Location
    Southwest Alaska
    Posts
    2,145

    Default How Much Brass Removed When Uniforming A Primer Pocket?

    On Winchester .223 brass about 0.06975 grains per case.



    This is 55.8 grains of shavings from a total of 800 cases. So now you know.
    Great spirits have always found violent opposition from mediocre minds. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence. Albert Einstein

    Better living through chemistry (I'm a chemist)

    You can piddle with the puppies, or run with the wolves...

  2. #2
    Member
    Join Date
    Apr 2006
    Location
    SwampView AK, Overlooking Mt. Mckinley and Points Beyond.
    Posts
    8,808

    Default

    OK, now I know.....

    Smitty of the North
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
    You can't out-give God.

  3. #3
    Member
    Join Date
    Jan 2007
    Location
    Southwest Alaska
    Posts
    2,145

    Default

    I was thinking of you when I made that little pile.
    Great spirits have always found violent opposition from mediocre minds. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence. Albert Einstein

    Better living through chemistry (I'm a chemist)

    You can piddle with the puppies, or run with the wolves...

  4. #4
    Member
    Join Date
    Aug 2007
    Location
    Eureka MT
    Posts
    3,048

    Default

    I must just not care enough as I've never even uniformed a primer pocket let alone weighed the results. I am curious though. Where does this remove material? Is it just to flatten/uniform the bottom of the primer pocket? I assume it cuts to a predetermined depth. I do uniform flash holes and deburr the front of the flash hole. What is the advantage of uniforming the primer pocket?

  5. #5
    Member
    Join Date
    Jan 2007
    Location
    Southwest Alaska
    Posts
    2,145

    Default

    The idea is to make each case as close to exactly like every other case. So we trim to the same length, de-burr the flash holes, and uniform the pockets.

    Uniforming the pockets allows for each primer to be seated to the same depth so the firing pin doesn't have to push the cup down onto the anvil differently each time: more consistent primer ignition.

    After all this: weigh the cases looking for the 95% that are the same weight to remove lighter (more internal volume), and heavier (less internal volume), cases. Phew!
    Great spirits have always found violent opposition from mediocre minds. The latter cannot understand it when a man does not thoughtlessly submit to hereditary prejudices but honestly and courageously uses his intelligence. Albert Einstein

    Better living through chemistry (I'm a chemist)

    You can piddle with the puppies, or run with the wolves...

  6. #6
    Member
    Join Date
    Apr 2006
    Location
    SwampView AK, Overlooking Mt. Mckinley and Points Beyond.
    Posts
    8,808

    Default

    rbuck351:

    Basically, the PP Uniformer squares the bottom edges inside the PP, and usually takes some off the bottom, depending on how UN-uniform the PPs are in the first place. It makes them SAAMI, and uniform.

    The purpose, is more uniform ignition and therefore better accuracy. The side-benefit that I find advantageous, is that primers will then easily, seat below flush with the case head.

    According to the Sinclair International Catalog....

    "Primer pocket uniforming is a case preparation task that should be performed each time you reload. The Sinclair Primer Pocket Uniformers are designed to cut the depth of primer pockets to the correct SAAMI specification and to clean the carbon out of the primer pocket after each firing.

    Why is uniforming the primer pocket so important? Primers are constructed with an anvil protruding from the bottom of he primer cup. When a firing pin strikes the primer cup, the priming compound is crushed between the anvil and the primer cup, causing the material to detonate. Variations in the depth of the pocket along with the priming operation can alter the effect of the firing pin blow. The proper use of a Sinclair Primer Pocket Uniformer allows the handlooader to cut the primer pockets to a uniform depth. It is strongly recommended o use these tools when reloading fired cases as the carbon needs to be cleaned out prior to seating a new primer.

    There are 3 sizes, SP/SR, LR, and LP. AND some specialty ones. I suggest, you also acquire the Power Adapter or Adapters, also. Maybe one for each uniformer you buy. Sinclair makes theirs outta tungsten carbide. They don't wear out. I figger they are the best.

    You can also buy hand-type PP Uniformers from other manufacturers. Do a search on the Net for PP Uniformers.

    http://www.sinclairintl.com/.aspx/pi...ket-Uniformers

    Smitty of the North
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
    You can't out-give God.

  7. #7
    Member
    Join Date
    Aug 2007
    Location
    Eureka MT
    Posts
    3,048

    Default

    Guess I should get one to see if it makes a measureable difference. On the other hand, maybe I should get them just to make cleaning primer pockets easier. Also, I've never liked the rounded area in the corner of the primer pocket. Thanks guys. I wish this stupid work computer would let me access gun and reloading sights.

  8. #8
    Member
    Join Date
    Apr 2006
    Location
    SwampView AK, Overlooking Mt. Mckinley and Points Beyond.
    Posts
    8,808

    Default

    Quote Originally Posted by rbuck351 View Post
    Guess I should get one to see if it makes a measureable difference. On the other hand, maybe I should get them just to make cleaning primer pockets easier. Also, I've never liked the rounded area in the corner of the primer pocket. Thanks guys. I wish this stupid work computer would let me access gun and reloading sights.
    Oh Defin'Nootly, Defin'Nootly.

    I'll be proud of you.

    Smiddy uff da Naw'arth
    Walk Slow, and Drink a Lotta Water.
    Has it ever occurred to you, that Nothing ever occurs to God? Adrien Rodgers.
    You can't out-give God.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •