Primer Seating Depth?

Leaddog

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For years I have been using the Lee handheld primer seating tool and tray with good success. Recently, I purchased the Sinclair priming tool just for my match brass. What seating depth do you use when seating primers? I am loading Federal 210M primers into a Lapua .308 Win case.

The Sinclair needed adjustment so I've set it to .010 the best I can measure. So far, I'm not real impressed with this tool. I have better seating 'feel' with my Lee.

What do you think?
 

doc76251

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Re: Primer Seating Depth?

I always figured if you were uniforming the primer pockets that you push them in till they stop. Just say'n.

FWIW I just upgraded to the new Lee with the square tray. Much easier than chasing live primers that don't land on the round one.

Cheers,

Doc
 

mtrmn

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    Re: Primer Seating Depth?

    I know every thing is taken into consideration with benchrest shooters. But adjusting the seating depth on primers?? First time I've heard that one. Of course it's obvious by that statement I'm NOT a BR guy. I always push them til they bottom out and call it good. In my simple mind the only thing that matters is it's not sticking up above the brass and it goes bang when it's supposed to.
    smile.gif
     

    MALLARD

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    Re: Primer Seating Depth?

    you can feel better with your lee tool ?! i cant...

    i dont think much of my sinclair prime tool either.

    i seat my primers until they start to flatten out , i ran a test on round primers ( well not flat) versus flat primers , didn't really see much of a difference either way.
     

    leadbullet

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    Re: Primer Seating Depth?

    you want your primers seated bellow the base of the case, .005" is usually plenty, you can go deeper as long as your firing pin can reach them.
    cheers.
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    All I can say is WOW. If the BR community has decided that primer seating depth is critical, they are getting far along in the herd mentality. As with several sudden trends, this one has little merit for the average shooter and I am betting there are a few sane people left in benchrest.

    Of course, I'm new here and I have noticed a little bit of the same type of group think. Probably because the majority shoot and compete in service rifles or some type? Could be wrong about that, but a few of the issues that crop up are endemic here, and I have not noticed them on other shooting boards....along with a distinct majority of relatively new shooters. Some things seem like "settled science" like co-ax forster, .0001 shoulder bumps, OAL, and a select few match bullets.

    I am a big believer in uniforming the primer pockets, been doing it for years and I always seat to the bottom of the pocket since that is generally where the right angle proper seating is accomplished. Seating a primer until it is slightly distorted is a new one on me? I can't see any good come of it? Please feel free to continue, with my blessings, but this kid will opt out of that little trick. The problem is that in a few days, somebody will make a post seeking help having trouble flattening seated primers. That's just one example, of many issues I have seen here.

    There is nothing wrong with being new to handloading, but the reader needs to stick with the essentials and forget about the nuances that may, or may not have proven value.

    As far as the seated primer, the only real consideration is that it is at least flush with the case head. If it requires abnormal effort to accomplish this, plan B is indicated....which is the primer pocket uniforming tool. (it became standard with me more than ten years ago, for everything)

    Anyway, at that point, until proven wrong, I suggest seating the primer to the bottom of the pocket. The value of seating to a particular depth pertains to .01% of the shooting public, and even then, I very much doubt that they could support the practice with concrete data? BB

    edit: PS as far as flattening the primer goes, which is Mallard's business and I am not saying it is wrong, but. I think that you could disturb the compound possibly causing it to crumble and then, transporting along miles of washboard roads, (point down) this powder could (possibly) migrate into the case through the flash hole. Okay, I have zero proof, but I could see a problem developing. Okay, you can put me on ignore.
     

    armorpl8chikn

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    Re: Primer Seating Depth?

    I can do little to improve on what the Boss has stated above^^^.

    I will say that this one slipped by my radar and it is probably just as well. I have shot BR and as far as I know everyone has to seat a primer until the anvil is firmly seated. You do not want your firing pin finishing the job of primer seating. I use a Lee Auto Prime II. It is a press mounted tool and one of the few Lee products I will reccomend or use. I have no use for any of the hand tools as I have a better feel with my press and it is easier on my arthritis.
     

    dstewart51

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    Re: Primer Seating Depth?

    I have been handloading for 10 years but Im new to the 338Lapua. Recently I found the value in a primer pocket uniformer. The Federal 215M primers would not always seat past flush in new Lapua brass. Last weekend I sat down and spent half the day with the uniformer on all of my 338LM brass. Now I know they are all the same, most importantly, and they seat just under flush like they should.

    As far as a priming tool, I just use one of my presses. After thousands of rounds I just know what it feels like when the primer seats fully. I agree with Boss, if your distorting the primer case you went just a bit too far.
     

    Sprayed99

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    Re: Primer Seating Depth?

    I set my stuff to .003 to .005. I use a handprimer and used a small worm clamp as a stop. It speeds things up a bit and gives me a consistant depth case after case. Does it help with better accuracy? I have no idea as I did that when I started reloading, but hey the more you keep consistant the better in my book.
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    What I have noticed is that, contrary to the above drawing, the bottom of the primer pocket, especially in Lapua, has a radius in the corners and this is why the case is screaming for a primer pocket uniforming tool.

    Then, seat your primer with any type of tool and seat them all the way, by feel. I do not understand this reference to so many thousandths, like stopping at some predetermined distance that is short of the bottom of the pocket? Obviously, I have not seen this tool set up with a dial indicator, which near as I can tell is the only way to measure your depth in .001 increments?

    'splain me? BB
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    THANK YOU!

    A complete waste of my money. Looks kool though!

    Okay, look. You guys here, mainly shooting long range 308 stuff. That's hardly benchrest and I do not think those guys have converted to this thrilling device while I wasn't looking. Besides, why would you have to measure primer pockets that are not of a uniform depth? The bottom is still the bottom. Have them give me a call; Tech support, hello! I need to talk to whoever is humping this doggie.
     

    Leaddog

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    Re: Primer Seating Depth?

    Thanks for the good replies, especially Sinister who provided the drawing. I knew there was something like this out there.
     

    427Cobra

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    Re: Primer Seating Depth?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BuzzBoss915</div><div class="ubbcode-body">THANK YOU!

    A complete waste of my money. Looks kool though!

    </div></div>

    I agree 100%, its a solution looking for a problem, the club I belong to has a number of world class BR shooters, I notice most use either a RCBS or a Sinclair priming tool.
     

    armorpl8chikn

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    Re: Primer Seating Depth?

    I can tell you this. There are more than a few benchrest guys that read the reloading section on the Hide for daily giggles. The lengths that some are going to in handloading for a tactical rifle are simply unreal. I am a long time competitor over several disciplines and many folks here will thumb their noses at my loading regimen. Gadgets are great for showing off.
    <object width="425" height="350"> <param name="movie" value="http://www.youtube.com/v/nUnlp37CAkA&feature=related"></param> <param name="wmode" value="transparent"></param> <embed src="http://www.youtube.com/v/nUnlp37CAkA&feature=related" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"> </embed></object>
     
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    Kinsman

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    Re: Primer Seating Depth?

    I am not a bench rest shooter.
    I load and shoot primarily 3 calibers: 308 Win. ,300 Win Mag, and .223 Rem.
    I can consistently shoot 1 1/2 to 2 inches at 200 yds.(the length of my range)
    I full length resize, and trim to length.
    I do not anneal, ream, turn necks, weigh bullets, compare meplats,nor fill the case with water to compare volume.
    I shoot and have a lot of fun.
    No problem with those that do all these things to improve their accuracy at a thousand yards, but for a lot of shooters, and those new to reloading, it is not a necessity.
     

    JimGnitecki

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    Re: Primer Seating Depth?

    I use my Sinclair priming tool for .308 priming, set just as it came from the factory. I push the primer in until it just bottoms, without crushing it. I sue Lapua 308 cases.

    Randomly, I have measured the distance from the case surface to the primer durface after seating the primer. It is fairly consistently .008" and the ammunition seems to perform consistently.

    Since I am using it in a semiauto rifle, I consider it critical to fully seat the primer each time, so as to minimize the chance of a slamfire.

    Jim G
     

    9H_Cracka

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    Re: Primer Seating Depth?

    This text -

    "In my own testing, I have found that the best method is to clean the primer pocket (I don't uniform them) then, seat the primer until you feel it just touch, then apply a bit more pressure (not a lot) until you feel a second level of resistance just starting."

    and:

    "If you examine some new primers you'll see that the legs of the anvil stick out past the bottom of the cup. When the legs hit the bottom of the primer pocket you feel that first resistance. As you continue to apply pressure you bring the cup over the legs and then the second level of resistance begins as the center of the anvil begins to compress the pellet. Stop!"

    From this article -

    http://riflemansjournal.blogspot.com/2009/11/primers-seating-pressure-and-pre.html

    Further confirms the need for pressure beyond the anvil touching the bottom of the cup.
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    Regarding the above post. I will concede a trifling amount if, as stated, the primer pockets are not uniformed. At that point, (in some brass) you just about HAVE to use considerable force just to seat the primer flush!

    I only use Lapua in 223 and 243 so my experience is not vast, but it seems to me that Lapua primer pockets require the uniforming tool, almost as a necessity, to avoid the solutions being offered above.

    I have used, at one time or another, just about all brands and when using the tool, it doesn't take a very keen observer to notice how much material is being removed from those pockets. Sometimes, the base of the primer pocket is not touched, just the radius of the shoulder. I think Lapua brass requires primer pocket uniforming, more than others because it's made more beefy. Other brands, it's just kinda a nice thing to do, helps in (what's the word?) ......ah, uniformity!

    In summation, friends; I see no reason to alter my opinion whatsoever. Do yourself a favor, please use the primer pocket uniformer tool. Seat primers with one hand while you pick your nose with the other and pay very little attention because it's almost automatic, they all seat to the exact same depth, any idiot can do it just as well. It doesn't require a precision measuring instrument or some type of mystical feel for just the right amount of crush.

    BB
     

    9H_Cracka

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    Re: Primer Seating Depth?

    My uniformers have not come out of their bin for a decade now and your post does not persuade me otherwise.

    There is nothing magical about what I do when seating primers, though there is no shortage of people out there that do not understand how to seat them and have ignition problems as a result. The uniformer is not the holy grail of trouble free priming.
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    No shortage of people that don't understand how to seat primers and have ignition problems? Really? There is an epidemic of ignition problems?

    WHY WASN'T I TOLD? SOMEBODY HAS SOME 'SPLAININ' TO DO!

    Hello? Trouble free priming is the rule, not the exception, last I heard? I have never experienced a primer problem, so I guess I'm one of the lucky ones? Forty-four years, by the grace of God; not a single ignition problem and I am so blessed! Or, maybe I am doing something right? If that makes you wrong, so be it.

    Holy grail is your word, not mine, but as far as I'm concerned, a primer pocket uniformer is a nice little tool that addresses a persistent little problem. Period.

    Give it another look, Amigo; you will thank me. BB
     

    clmayfield

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    Re: Primer Seating Depth?

    The Sinclair tool just has to be adjusted so that you are seating "within the range." The point of the tool is to minimize leverage to give you more sensitivity for the feel. You do have to remove those spacer rings to get you in the right zone. If you are not firmly seating the primer when you squeeze the handle all the way, you need to remove a ring. If your primer is fully seated half way through the stroke, then you need to add a ring. It is pretty simple... and not much different than other tools out there. You shouldn't have to go 100% stroke every time.
     

    9H_Cracka

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    Re: Primer Seating Depth?

    Just got off the phone with a long time competitive shooter that was having ignition/priming troubles. He consulted with his smith, Al Warner. Al told him to stop uniforming his primer pockets.

    Do I need to post a picture of my belly button? Just wanted to confirm for you that I have one as well.

    I've personally witnessed 5 incidents in the last 2 years. Add a 6th for the mod Chiller here, Hugh, over the phone description.

    You must not get out much.
     

    JimGnitecki

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    Re: Primer Seating Depth?

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Carter Mayfield</div><div class="ubbcode-body">The Sinclair tool just has to be adjusted so that you are seating "within the range." The point of the tool is to minimize leverage to give you more sensitivity for the feel. You do have to remove those spacer rings to get you in the right zone. If you are not firmly seating the primer when you squeeze the handle all the way, you need to remove a ring. If your primer is fully seated half way through the stroke, then you need to add a ring. It is pretty simple... and not much different than other tools out there. You shouldn't have to go 100% stroke every time. </div></div>

    Based on what you say, I might need to take out one spacer ring, as I barely bottom the prime in the pocket before I run out of stroke room on the tool. I guess I'll pull out the Sincalir tool instructions.

    Jim G
     

    BuzzBoss915

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    Re: Primer Seating Depth?

    Get out much? Why would I need to? MSNBC pretty much keeps me informed about what I need to know.

    Truce, bro. I can see you are unconvinced, which does not surprise me.

    By the same token, your explain strikes me as worthless, except for the distressing news that we have grown men out there, that don't know how to seat a friggin' primer!

    BB