Primer Anatomy & Thickness Variance
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- čas přidán 10. 07. 2024
- In this video you will learn about individual components of primers and their dimensional differences. Then we'll go into how to ensure the primers are seated properly for reliable ignition. Ignition tuning and primer seating depth testing will be covered in a later video.
- Sport
This was so helpful. Thank you and looking forward to seeing more of your content on Erik’s site. I find that everyone on his site is there to learn instead of challenging knowledge just to either be argumentative or prove that they know better (even if they dont). I still quite dont get the aggression towards the Prometheus.
I'm new to precision reloading, precision rifles, and competitive shooting, and I've watched EVERYONEs channels and content. I have a paid membership with you and so far only you due to the fact that I walked away from my first experience with your content with new knowledge that hadn't been discussed elsewhere. This channel should and probably WILL end up being THE channel for learning as much as you possibly can. Thank you for all you do to help all of us!!
Very kind!
Every time I watch one of your videos, I always come away with more knowledge. Thank you
Makes me scratch my head in a good way. Great information. Thank you and looking to seeing more videos related to this.
And we also appreciate your participation there! I've been enjoying the knowledge you've been sharing.
Thank you Greg for putting out that kinda content. You are a real good teacher. Dont stop digging... I love rabbit holes!
Nice content! I love my CPS and must say it is solid and is very smooth in operation and simple to set up. Very happy with it, Thanks Greg
Great content Greg! Keep it coming.
Yesterday I was creating 6mm ARC brass from PMC X39 cases. (Try that in your spare time!) And to amuse myself, during some of the mindless trimming and turning, I switched on you and Erik. I should have known better. In one "rabbit-hole day" I found myself like Union Major General William S. Rosecrans after his defeat at Chickamauga, "Like a duck hit on the head," according to Abraham Lincoln. My knowledge base has expanded twofold. And I've been doing this a while....
I am still recovering this morning. But, all this to say, you guys work well together. And you, in particular, have a spirit about you that seems familiar. I wonder what that is?
As always great information. Thank you!
New subscriber today Greg. Excellent interview with Erik by the way.
Great to hear you are a great resource for information
Variations in rim thickness should also play a role since the seating tool indexes at the top of the rim and the measuring tool indexes at the head face of the cartridge. Minimum variation certainly with quality brass - I found less than 0.5 tho differences on 6 Dasher Alpha brass. And the additional 2 tho crush you recommend should take care of that. Another factor affecting ignition timing is headspace, as the brass is pushed against the shoulder by the bolt (or firing pin) before the firing pin starts crushing the primer cup. Precise brass sizing is really key here...
Greg. Great investigative work. Would love to see the next step in the analysis. Using the measurements and then using seated in cases such as a 6 PPC and shooting in rail gun testing group size and SD would be great.
What depth are you seating your primers at ? Factory shells are 0.004" below flush. I get better groups with 0.007" below flush. some like 0.008" to 0.010" below. You got about 0.013" to 0.015" below flush before you bottom out.. Better to go lower for floating firing pin guns. (AR's, BLR's ,BAR's) Frankford Arsenal Platinum Hand Priming Tool can be adjusted to 0.015 below flush.. I cant get any CCI 200 or250 primers to go off in my BLR, someone said its the Nickle coating on the cup ? Any suggestions on a soft primer. some say Fed210 and 215's are easy to set off but I see federals and CCI are owned by the same company now..
Greg, I really appreciate the videos and all the effort that you have put into them and your product. I have watched your interview with Eric and Brian Zolnikov's videos on primer seating depth testing. I tried seating to .008 below flush with BR4's, and then let them sit for a few days and then remeasured the depths. Out of ten pieces 7 had changed to .004 to .006 and only 3 held at .0075.
Have you done any testing on this phenomenon to see if that change matters? I shoot primarily 1-300yd benchrest score and group.
Thanks!
Mike
I haven't seen that... but I only did one test, overnight. Perhaps I should re-visit that. :) It makes sense when you think about it. Those primers are getting squeezed hard. I suspect a loose pocket would for sure cause it.
@@primalrights Thanks for the quick reply! The brass I used had been fired 10x in a PPC using moderate loads primarily. I imagine that fresh brass would provide better "grip", but over time the pockets would change/vary their grippyness (technical term) I would have to think...?
@@mikes5918 They certainly do. That's one big reason I've been super impressed with the new Alpha OCD cases. The firing to firing consistency is the best I've seen. I assume you're running lapua cases? I would consider 10x firings with moderate loads to be not many firings. Should still have a healthy pocket.
After watching Brian's video(great channel and videos where he actually tests to statistical relevance a lot of the time!) where he talks about the optimum "crush" to be 0.009" (he tested all the way to 0.013") I started to do an in depth measuring and testing which involved making a couple measuring tools in the machine shop. I have a feeling there's something off about the way he's measuring it because I cannot even achieve 0.007" of anvil crush on CCI BR4 primers(same as tested) without metallic deformation occurring on the primer cup. This takes an extreme amount of force as well. I also disassembled a primer and there's less than 0.010" of anvil protruding from the cup so to get those levels of crush you'd have forced the entire anvil into the cup. My guess is that some of what he's measuring is metallic deformation. In my case to get 0.002" of anvil crush the primer would only be ~0.004" below the rim of my 220 Russian(6ppc) Lapua brass. (my BR4 Primers measure 0.1205-0.1215 and pockets were 0.123")
So I'd hazard to guess that might be why you're getting so much spring back. If we're using the same brass/primers and you tried seating to 0.008" below the rim then that would equate to about 0.006-7" of anvil crush. In my testing I seated a few to 0.008-9 but they had a visible deformation where the seater had indented the cup. I haven't tried measuring them again since and they were relegated to warm up rounds only but now I'll go back and see what they measure now and update here.
Greg does this matter in say a Rem 700 Vs a High end F Class rifle?
Thanks Greg, great video and well presented content. I would love to purchase a CPS, but I'm located in Australia. Will Primal Rights be shipping outside the US anytime soon?
Thank you once again.
Steve, lots of Aussies have CPS's. :) You can order from our international distributor, Graf & Sons.
Nice to have a professional do in depth/close up explanation, great video and explanation. I'm a noob so silly question, Do you have to worry about setting primer off while crushing the anvil? I assume the pressures used are below ignition pressure compared to firing pin strike?
I’ve never had it happen.
The number of variables in target shooting that could potentially affect the bullet placement on the target are almost too numerous to nail down.
This dudes legit! Always wanting to help others , unlike EGO cortina (Eric cortina) who’s out to stroke himself lol
Am I understanding correctly? Essentially we want to find our shallowest primer, deepest pocket, and average the depth of seating so that even the deeper pocket/shorter primer marriage will have some degree of anvil compression without a shallower pocket/longer primer marriage being set to cup contact in the pocket, yes?
i load pistol and rifle i have a video of a pro pistol shooter he takes 100 primers lays them all upside down on a tray looks for all the anvils is all there & the color under it all there a seeing check every primmer he loads 100's of pistol rounds a miss fire might cost him a win! its bad!
A little bit about different brands and types of primers.
Which ones to use, when and why.
All CCI and Remington primer, plus Winchester's small pistol are the safest to use in automatic priming tools.
Federal burns hotter and cleaner, yet are according to the Richard Lee manual "one tough dragon to control in the automatic priming systems".
Modern Reloading Second Edition Richard Lee Revised 2021, page 60:
To find out why some brand primers explode violently, I talked to an expert, Dave Anderson, now retired from CCI. He told me primers are charged with one of two types of charging compound. One is called "basic" and the other is "normal." The primers that use "basic compound" must not be used in Lee Priming tools because an accidental discharge is very violent. The "normal compound" is less violent and causes little damage to the tool. The user is easily protected by safety glasses.
Metallic Cartridge reloading, Robert S. L. Anderson, page 20:
In the firearms industry there are two types of lead styphnate primer compounds - "normal" and "basic." There are presently four manufacturers of primers in the U.S., and all of them except one uses the normal lead styphnate primer compound. Federal is the only manufacturer that presently uses basic . The common ingredient to all small arms primers is lead styphnate of which there are several different varieties. Basically it is in crystalline form and is very explosive. Normal lead styphnate is composed of large irregular crystals, which are slightly acidic when wet, somewhat more brisant at lower temperatures (good for military use), and they burn with a cool flame at ambient temperatures. However, it is somewhat harder to get an even mix of components in normal lead styphnate primers because of the larger irregular crystals and the fact that the "mix" often requires some metallic fuels (such as powdered aluminum) to help make a magnum primer. Basic lead styphnate is composed of small regular crystals and unlike the normal mix is not as acidic and will not attack primer cups when wet. Basic lead styphnate is easier to mix than normal variety and there is no need to add metallic fuels. The basic primer flame is very hot and will easily ignite most powders and therefore Federal does not offer a magnum pistol primer. However this style primer is slightly less brisant at very low temperatures (- 20degrees F. to - 40 degrees F.) which would make normal primer more suitable for military purposes.
Metallic Cartridge Reloading, All New Third Edition, M.L. McPherson, page 29:
Certain brands of primers might be unsafe to use in some priming tools like Lee's AutoPrime because of the potential for mass detonation. With these tools, should an operator detonate one primer, as can happen when a handloader tries to seat one primer on top of another, the detonation subjects other primers in the tray to shock and an incandescent flash. If this shock and flash can detonate a second primer, there is the potential that most or all (perhaps 100 or more) primers in the tray might detonate en masse. Such a simultaneous detonation would be a disaster. Lee has tested all available primers and, excepting CCI and Winchester, all brands produce an unacceptable number of mass explosions when the primer being seated is forced to detonate (by heating in a remote explosion-proof box). By comparing Federal and CCI primers, we can gain some understanding why brands very in this regard. Federal primers do not have a foil covering over the primer pellet; an application of a type of paint replaces the foil. That sealant is easily ignited and highly flammable, possessing a very low kindling temperature. These are beneficial characteristics; among other things, they help reduce combustion residues. However, use of this pellet sealant makes these primers very easy to ignite. Exposure of the open front of the cup to the flash from an adjacent primer easily does the job! Conversely, CCI primers have a paper foil almost completely covering the front of the pellet. This foil deters pellet ignition because it is only moderately combustible and has a relatively high kindling temperature. A short duration flash from a primer is unlikely to ignite the foil or penetrate through it to ignite the pellet underneath.