Home Main Category General Firearms

Uniforming Primer Pockes - Why?

ZeeZee Senior MemberPosts: 27,466 Senior Member
Why am I doing this?

This question popped in my head just now as I was uniforming primer pockets of some factory brass I just shot today. As I sat there doing so, I thought........."Why the Hell am I doing this?" I just shot a .162" three shot group with this factory loaded brass this morning.

Looking over several of the groups I've shot with this factory ammo in the past, it seems that if I do my part.........this brass in factory loaded form will produce regular groups in the .1s".

So, I'm asking an honest question. Why..........after the brass is once fired..........am I then taking that brass and uniforming the primer pockets? Seriously, I would like clarification as I've been doing this step for years now. And, I JUST came to the point of.......WHY?

Am I improving the brass that much? I can't shoot .1" groups at will in either pre-uniformed or post uniformed. But, they are regular enough with both to make me wonder if that step is the reason or that I just get things right on occasion and other times......I don't.

I'd REALLY like to start skipping this step. But, I'll continue if there is a legit reason. I just think I finally woke up, though. Am I REALLY good enough a shooter to tell the difference? If the brass groups well either way, then it's more on me than the extra step of uniforming the pockets. If that's the case............screw uniforming them!!!!!

Help!!! Suggections? Recommendations? I come groveling to those that got me started in reloading in the first place.
"To Hell with efficiency, it's performance we want!" - Elmer Keith
«1

Replies

  • ZeeZee Senior Member Posts: 27,466 Senior Member
    cpj wrote: »
    No one can prove to me it makes a difference. Making sure the flash hole is prepared properly. Yes. But the pocket being uniform? Yeah. Might start calling you Dan.

    Hey, I did this step because I was told to do so by YOU knuckleheads. Now I'm wondering...........why?
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • Elk creekElk creek Senior Member Posts: 7,372 Senior Member
    Brass is better today than yesteryear! I clean out the carbon that's it. If your getting good results why go through the extra steps? For a super touchy cartridge of a wildcat reformed job maybe but a gun/cartridge combo shooting in the .1s fogetabadit!! More time shooting.
    Aim higher, or get a bigger gun.
  • breamfisherbreamfisher Senior Member Posts: 13,877 Senior Member
    I don't do any of that. My .308 shoots .2"-.5" groups if I do my part with proper ammo loaded out of Lyman Full-Length Resizing dies. Not even top quality competition ones. My AR shoots as well as my eyes will allow it to with a red dot. I don't even deburr the flash holes or clean the primer pockets...
    I'm just here for snark.
  • BigDanSBigDanS Senior Member Posts: 6,992 Senior Member
    cpj wrote: »
    No one can prove to me it makes a difference. Making sure the flash hole is prepared properly. Yes. But the pocket being uniform? Yeah. Might start calling you Dan.

    Hey! I resemble that remark!

    I am not as good a shot as you are Zee, and my rifles are not nearly as tuned. I am still pretty much a rookie rifle reloader, but it seems to me the more uniform your pressure vessel is the more uniform your pressure curve will be.

    I did something fun today. I wrinkled a case while loading my .243's so I pulled the bullet and powder and had this primer in a bad case just waiting to be popped. I put on my safety glasses and hearing protection, clamped the case in the vice, got out a nail and a hammer detonated that Winchester large rifle primer. It was pretty vigorous! I also lit off some spilled H4350 ( about 10 gr ) just to see it burn. It was a great reminder visually of what is going on inside the casing.

    Ignition from the primer is not gentle. It is forced through the primer pocket hole into the powder, and when the powder is stacked up it essentially burns one spot. That ignition point has to expand into the rest of the powder and if it isn't uniform I can see it igniting differently, either a hotter spot or a less hot spot in the powder.

    Also powder does not "explode" unless under pressure, it just burns. In my mind a uniform hole / pocket for the ignition to go through provides a more consistent start to the reaction.

    So I am a very anal reloader, trying to get everything as close to the same as possible. I don't know what I am going to do if I ever get a Hornady OAL length gauges for my 30-06, .308, .243, and .223. I am even considering chamber casting to know my best OAL's.

    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • JayJay Senior Member Posts: 4,349 Senior Member
    I've never done it. Don't have the tools to do it. After depriming, I clean the priper pockets on my RCBS case prep machine, which I also use to chamfer and debur cases when they need it. Aside from cleaning and resizing the brass, thats about all I do to it. Clean, resize/deprime, trim (if needed), chamfer, deburr, clean primer pockets. That's it. But I don't shoot .1 groups, either. .3-.4 is about the best I've got.
  • ZeeZee Senior Member Posts: 27,466 Senior Member
    Dan,

    All of what you said seems to deal more with the flash hole than the primer pocket.

    I am meticulous in other areas of loading. But, I don't weigh brass, primers, bullets to sort by weight but, still get ammo that is better than me on a drop of the hat basis. I'm just beginning to think that uniforming the pockets ain't making enough difference either.
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • ZeeZee Senior Member Posts: 27,466 Senior Member
    BigDanS wrote: »

    So I am a very anal reloader, trying to get everything as close to the same as possible.
    D

    Do you see a difference?
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • BigDanSBigDanS Senior Member Posts: 6,992 Senior Member
    Zee wrote: »
    Do you see a difference?

    Honestly, I am not good enough to see a difference. I suppose I try everything possible to eliminate any variable except for me and the gun. Then I know the gun's potential.

    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • Gene LGene L Senior Member Posts: 12,576 Senior Member
    If you shoot benchrest, it may make a .01" difference. I once prepared maybe 40 rounds of brass and uniformed the pocket and the primer hole. Can't say it made any difference, but it kept me out of the bars for a while.
    Concealed carry is for protection, open carry is for attention.
  • tennmiketennmike Senior Member Posts: 27,457 Senior Member
    Depends. If it's brand new brass I deburr the inside of the primer hole. If it's range pickup brass, I sort by brand, deprime, deburr primer hole, and run it through the Dillon primer pocket swager. Some primers are crimped on range brass (mil surp) and I start with all primer pockets being uniform. I don't know that it makes a difference other than not squeezing a primer in a hole too small and crumbling the primer compound. Anyway, not like I'm covered up with things to do. :tooth:
      I refuse to answer that question on the grounds that I don't know the answer”
    ― Douglas Adams
  • BufordBuford Senior Member Posts: 6,721 Senior Member
    I never gave uniforming primer pockets a thought. I never found it necessary.
    Just look at the flowers Lizzie, just look at the flowers.
  • jaywaptijaywapti Senior Member Posts: 5,032 Senior Member
    I stopped uniforming primer pockets long ago, the only thing I do is deburr the flash hole, and clean after firing. Today with old eyes almost any load shoots better than me. A perfect example is with my 22-250 I shot a 5 shot 7/8" group, a buddy of mine, a benchrest shooter shot a 5 shot group into 3/8" , same rifle and loads.

    JAY
    THE DEFINITION OF GUN CONTROL IS HITTING THE TARGET WITH YOUR FIRST SHOT
  • Big ChiefBig Chief Senior Member Posts: 32,995 Senior Member
    I have some brand of foreign brass (PMC/others) that primers were hard to seat and so took a tool to them. Usually, no I don't.
    It's only true if it's on this forum where opinions are facts and facts are opinions
    Words of wisdom from Big Chief: Flush twice, it's a long way to the Mess Hall
    I'd rather have my sister work in a whorehouse than own another Taurus!
  • jbohiojbohio Senior Member Posts: 5,615 Senior Member
  • JayhawkerJayhawker Moderator Posts: 18,118 Senior Member
    Reloading is one of those activities that allows one to be as meticulous (spelled A-N-A-L) as one desires the process to be...uniforming primer pockets is one of those steps I can accomplish my goals without.....
    Sharps Model 1874 - "The rifle that made the west safe for Winchester"
  • BigslugBigslug Senior Member Posts: 9,327 Senior Member
    Disturbing how time flies. . .I think Dad and I started handloading nearly 30 years ago, and the accuracy-in-earnest stuff started maybe 20 years ago. At around that point in time, we saw brass that made you want to do this - jagged, off-center flash holes formed with a punch and wildly varying pocket depth.

    In theory, more uniform depth gets you more uniform lock time from primer strike to primer pop. I wonder if anyone ever actually computed the nanoseconds that would amount to. . .

    We went through a very intense period of pocket uniforming, neck turning, and sorting cases by weight. Three things changed this: #1, we woke up one morning and suddenly realized that we were shooting NRA Highpower, deer rifles, and the early games that lead to F-class - - NOT Benchrest; #2, the brass industry in general got a whole lot better, and we realized that after our time prepping cases was factored in, it was cheaper to buy Lapua and Norma brass than to fritter away our lives tuning a lesser product; and #3,we came up with the loading process that I've outlined elsewhere that works to minimize the effect of internal variables.

    So, we've basically got the process down to where getting jacketed to shoot under 1.5 MOA is usually pretty easy, getting under a 1-MOA is no huge challenge, and squeezing 3/4 MOA out of the dedicated target guns doesn't burst any blood vessels. Sometimes we get luckier at that level of effort. Anything more than that would start to require going back to the crazy-anal measures that began to suck all the joy out of the game.

    I've said it elsewhere and I'll say it again here - KEEP IT REAL! If you are already creating ammo that can reliably shoot groups inside a deer's eye socket from 300 yards, what functionally is to be gained by trying to improve it?
    WWJMBD?

    "Nothing is safe from stupid." - Zee
  • ZeeZee Senior Member Posts: 27,466 Senior Member
    Just for clarification, the brass in question starts life as Hornady 168gr A-Max TAP Precision and has "Match" written on the headstamp. For whatever that's worth.

    I just don't feel like uniforming the pocket anymore. That is the one step that takes the fun out of handloading. The one step I hate.

    But, regardless the brand, I don't think I'll do it to any of the new brass I use either. Whether Winchester or Remington.

    Just kinda burned out on that step, I guess.
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • N320AWN320AW Senior Member Posts: 648 Senior Member
    If you are shooting the size groups you mentioned, there is absolutely no reason to mess with the primer pockets unless you are a robot. What I am saying is that the "human factor" comes into play and this is something that even excellent shooters in general have to contend with, although most won't admit it. One can have the finest, most accurate rifle, reloads, etc., but the shooter of the gun is the major contributing factor that affects accuracy. Forget primer pockets etc. You're wasting your time.
  • BigDanSBigDanS Senior Member Posts: 6,992 Senior Member
    Zee wrote: »
    Just for clarification, the brass in question starts life as Hornady 168gr A-Max TAP Precision and has "Match" written on the headstamp. For whatever that's worth.

    I just don't feel like uniforming the pocket anymore. That is the one step that takes the fun out of handloading. The one step I hate.

    But, regardless the brand, I don't think I'll do it to any of the new brass I use either. Whether Winchester or Remington.

    Just kinda burned out on that step, I guess.

    What could you be shooting at that requires better than .1 to .2 MOA precision? Seriously, I have never shot a group with a center fire that was less than .5 MOA.

    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • ZeeZee Senior Member Posts: 27,466 Senior Member
    BigDanS wrote: »
    What could you be shooting at that requires better than .1 to .2 MOA precision? Seriously, I have never shot a group with a center fire that was less than .5 MOA.

    D

    Personal desire. No other reason.
    "To Hell with efficiency, it's performance we want!" - Elmer Keith
  • JermanatorJermanator Senior Member Posts: 16,244 Senior Member
    BigDanS wrote: »
    Seriously, I have never shot a group with a center fire that was less than .5 MOA.

    Pitch that Lead Sled and do your rifles a favor-- you are embarrassing them...
    http://www.midwayusa.com/product/412484/caldwell-rock-front-shooting-rest
    Reason obeys itself; and ignorance submits to whatever is dictated to it.
    -Thomas Paine
  • BigDanSBigDanS Senior Member Posts: 6,992 Senior Member
    Jermanator wrote: »
    Pitch that Lead Sled and do your rifles a favor-- you are embarrassing them...
    http://www.midwayusa.com/product/412484/caldwell-rock-front-shooting-rest


    I have one.

    I prefer the Lead Sled mostly because I am too tall for the benches at the range. If they built them up another foot I could use them, but at "standard height" I have to contort into yoga poses to get in line with the scope. Most of the time I have to kneel, instead of sit to get low enough to shoot the rifles when they are rested.

    D
    "A patriot is mocked, scorned and hated; yet when his cause succeeds, all men will join him, for then it costs nothing to be a patriot." Mark Twain
    Alcohol, Tobacco, Firearms and Explosives.... now who's bringing the hot wings? :jester:
  • snake284snake284 Senior Member Posts: 22,429 Senior Member
    BigDanS wrote: »
    Hey! I resemble that remark!

    I am not as good a shot as you are Zee, and my rifles are not nearly as tuned. I am still pretty much a rookie rifle reloader, but it seems to me the more uniform your pressure vessel is the more uniform your pressure curve will be.

    I did something fun today. I wrinkled a case while loading my .243's so I pulled the bullet and powder and had this primer in a bad case just waiting to be popped. I put on my safety glasses and hearing protection, clamped the case in the vice, got out a nail and a hammer detonated that Winchester large rifle primer. It was pretty vigorous! I also lit off some spilled H4350 ( about 10 gr ) just to see it burn. It was a great reminder visually of what is going on inside the casing.

    Ignition from the primer is not gentle. It is forced through the primer pocket hole into the powder, and when the powder is stacked up it essentially burns one spot. That ignition point has to expand into the rest of the powder and if it isn't uniform I can see it igniting differently, either a hotter spot or a less hot spot in the powder.

    Also powder does not "explode" unless under pressure, it just burns. In my mind a uniform hole / pocket for the ignition to go through provides a more consistent start to the reaction.

    So I am a very anal reloader, trying to get everything as close to the same as possible. I don't know what I am going to do if I ever get a Hornady OAL length gauges for my 30-06, .308, .243, and .223. I am even considering chamber casting to know my best OAL's.

    D

    Actually, smokeless powder should never explode, especially under pressure since we make use of it under usually extreme pressures, that is if your definition of explode is what mine is. At work we considered an explosion as a Detonation or a rapidly accelerating Deflagration. A detonation doesn't turn corners and will blow out adjacent walls. It generates destructively high pressures.

    A detonation is where you have a flame front at or above the speed of sound. A deflagration is where the flame front is below the speed of sound. This is considered a burn not an explosion. And even under pressure, and especially under pressure it is still a burn. Burns or slower flame fronts generally generate usable pressure levels, whereas explosions create destructive pressure waves.

    For instance in and automotive or truck engine. If your gasoline engine is pinging (Sometimes called detonation or pre-detonation) it usually needs a higher octane or rather slower burning fuel(This is providing your timing isn't too far advanced or you don't have some other problems. This pertains in general if everything else is up to spec.). The fuel in the cylinder is detonating as the pressure increases. This can cause damage to your engine and is usually occuring before the piston reaches Top Dead Center.

    The reason why you have slow burning and fast burning powders is because different calibers and cartridges need different powders with different burn rates. The slower burners generally work better in long barrels and over bore cartridges. The fast burners normally work better in larger diameter barrels with a more generous expansion ratio. You get a more usable pressure curve and more shove on the bullet with the correct powder in a given rifle. Note that this is a very simplified explanation. In reality things are a little more complicated, so unless you are a certified ballistician, take my advice and don't try and reinvent the wheel, just do like most of us and go by a book on listed powders for specific loads in specific cartridges. You might live longer like that.

    OK Thread highjack over, back on subject:

    Now as for primer pocket uniforming. Does it help? I'm not entirely sure but suspect it is probably one of those deals where shooting a more normal average rifle you will never see the difference or at least not enough difference to make it worth while. However, if you're into serious competition shooting a really potentially accurate rifle, it might make a difference where hundredths or thousandths of inches might make the difference in a winning group and an also ran.
    Bye the way, I do it anyway, just because I can, LOL!
    Daddy, what's an enabler?
    Son that's somebody with nothing to do with his time but keep me in trouble with mom.
  • JermanatorJermanator Senior Member Posts: 16,244 Senior Member
    cpj wrote: »
    A 2x4 cut into pieces and screwed into a platform would make a platform to set it on. It would still be plenty stable. Much better than that P O S lead sled.
    Yep. I have the same problem Dan does. I can usually make it so I can sit lower-- like bring my own stool or chair. With any decent handload, 1/2" groups should be a common occurrence. So either your handloads suck horribly (which I doubt) or your shooting rest sucks (extremely likely). You will know once you get yourself into a good solid rest-- you will start noticing your gun move with your breathing and heart beat-- and you will notice things like your breathing and cheek weld. I don't think your loads are the issue, it is all the other stuff that is getting you. There is no point in beating yourself to death over your loads until you get the rest of the stuff under control.

    Once you do, I bet you will be surprised.
    Reason obeys itself; and ignorance submits to whatever is dictated to it.
    -Thomas Paine
  • snake284snake284 Senior Member Posts: 22,429 Senior Member
    BigDanS wrote: »
    I have one.

    I prefer the Lead Sled mostly because I am too tall for the benches at the range. If they built them up another foot I could use them, but at "standard height" I have to contort into yoga poses to get in line with the scope. Most of the time I have to kneel, instead of sit to get low enough to shoot the rifles when they are rested.

    D

    At our range we have concrete benches that just don't move. But they are reasonably high enough for most anybody to line up on the scope especially since the stools are adjustable for height. So far, Wheelsman is the only forum member to go there with me, but I think he was impressed. But we had the assistance of a real bench rest shooter to help design them. They are right at 30 years old but still work great

    BayGCRifleRange002.jpg
    Daddy, what's an enabler?
    Son that's somebody with nothing to do with his time but keep me in trouble with mom.
  • JayhawkerJayhawker Moderator Posts: 18,118 Senior Member
    BigDanS wrote: »
    What could you be shooting at that requires better than .1 to .2 MOA precision? Seriously, I have never shot a group with a center fire that was less than .5 MOA.

    D
    Zee wrote: »
    Personal desire. No other reason.

    That...and a lot of folks get what they settle for.... I like to wring every bit of accuracy I can get out of my rifles....it's one of those things that floats my boat...
    Sharps Model 1874 - "The rifle that made the west safe for Winchester"
  • slamfireslamfire New Member Posts: 3 New Member
    It may make a difference to bench rest types, or reloading equipment manufacturer’s, but I think any accuracy improvements are in the noise. There are just too many variables.

    I do know my F Class friends, some of whom have won National Championships, they just buy Lapua small primer brass, then load and shoot the stuff.

    The only time “reaming” is of any importance would be with semi automatic mechanisms. It would be a safety concern if a shallow primer pocket allowed a high primer. According to CCI in the article, Mysteries And Misconceptions Of The All-Important Primer http://www.shootingtimes.com/ammo/ammunition_st_mamotaip_200909/ several conditions have to be met for a primer to ignite. It turns out high primers are the most common cause of mis fires. If the anvil is dangling in the air, or the primer cake is not wedged between the anvil and the primer cup, the primer will mis fire. You read posts on this all the time, the reloader did not seat the primer deep enough. However, if you stick spacers in your primer pockets, or, you have shallow primer pockets, then you have the potential for a fully seated anvil and a high primer. Then in an automatic gun mechanism, you could have a slamfire just due to the bolt face hitting the high primer. So, reaming pockets to depth for ammunition used in semi autos is a reasonable measure.
  • JayhawkerJayhawker Moderator Posts: 18,118 Senior Member
    Our range benches were designed too tall to sit at and too low for a normal human to stand at. To combat this, I got a portable shooting bench that's made of 3/4" plywood that breaks down and fits in a bag....nice and solid and the top can be flipped over to accommodate left/right hand shooters....similar to this

    http://sharpshootershootingbenches.com/
    Sharps Model 1874 - "The rifle that made the west safe for Winchester"
  • snake284snake284 Senior Member Posts: 22,429 Senior Member
    Jayhawker wrote: »
    Our range benches were designed too tall to sit at and too low for a normal human to stand at. To combat this, I got a portable shooting bench that's made of 3/4" plywood that breaks down and fits in a bag....nice and solid and the top can be flipped over to accommodate left/right hand shooters....similar to this

    http://sharpshootershootingbenches.com/
    Heck if it works for you that's all that matters. I like simplicity too. And for what i do what you've got there would do it all. I was mainly addressing Dan's issue with height and Our range addresses that with the adjustable stools. And the tables are pretty well suited to most of us.
    Daddy, what's an enabler?
    Son that's somebody with nothing to do with his time but keep me in trouble with mom.
  • Six-GunSix-Gun Senior Member Posts: 8,155 Senior Member
    Linefinder pointed out to me some time ago when we were discussing this primer pocket issue over the phone: about the only real reason to uniform the primer pockets is to make subsequent pocket cleaning that much easier. He's right. I find it much simpler to clean the carbon out of the flat, uniformed pocket than the radius-rounded one that most factory brass has.
    Accuracy: because white space between bullet holes drives me insane.
Sign In or Register to comment.
Magazine Cover

GET THE MAGAZINE Subscribe & Save

Temporary Price Reduction

SUBSCRIBE NOW

Give a Gift   |   Subscriber Services

PREVIEW THIS MONTH'S ISSUE

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Get the top Guns & Ammo stories delivered right to your inbox every week.

Advertisement