Metric primers?

nettlle

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Every now and then I will run across reloading information talking about metric primers. I am trying to figure out if there is any difference between metric and standard primers.
 
I been trying to look up the difference between them and not having any luck.
I think what you will find is the “dimensions” are the same but the rounding error in converting from mm->inch and vice-versa creates some variation.

Example: The 9mmMakarov is a Russian/Soviet cartridge. It measures 9.2mm, not 9mm. The CIP standard calls for a case length of 18.10 with a tolerance of -0.25mm. That gives a range of 0.712” down to 0.703”. The SAAMI standard for the same cartridge calls for a case length of 0.713 with a tolerance of -0.010”. That gives a range of 0.703-0.713”. There’s only a thousandth of an inch difference, but it’s a difference.
There are other examples and there are plenty of arguments about how much or how little difference it makes but the bottom line is “Small Pistol” is a standard for Boxer type primers and it’s up to the manufacturer to stay inside the tolerance. If the manufacturer is measuring metric and converting to Imperial or SAE or something else (like Arshins, for example) then there will be some variation and it’s up to the consumer to adapt.
IMG_2380.jpeg
 
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I have heard of boxer & berdan primers but I've never heard of metric primers.
Most ammo coming from metric countries have berdan primers could that be what he is talking about?
 
Are metric primers specific to metric calibers? Are both 9mm Makarov and 9mm primers available?

Where dos it say that these are metric?
No. Each manufacturer is responsible for producing a product which meets the inspection requirements of their market. In converting from metric to inch there is some rounding error which can (and has) result in fitment failure. The problem is easy to solve but some people find it annoying to deal with. I think the problem is with the end user, not the part, but that’s just me. I’m pretty flexible.

It might help if you read the SAAMI standards articles on their website. They explain variances and tolerances very well.
 
So much mis-information in one thread.

Lets try to correct some odd beliefs

I have heard of boxer & berdan primers but I've never heard of metric primers.
Most ammo coming from metric countries have berdan primers could that be what he is talking about?
No, the difference between Boxer primers and Berdan primers have nothing to do whether they are metric

Are metric primers specific to metric calibers? Are both 9mm Makarov and 9mm primers available?
Primers come in 4 designations: Small Pistol (SPP), Small Rifle (SRP), Large Pistol (LPP), and Large Rifle (LRP)...they aren't caliber specific. Both cartridges in your question are metric calibers and use SPP

Wolf, Ginex, are steel cases & are berdan primed.
Wolf is an importer and doesn't manufacture ammunition. They import ammo with both brass and steel cases, also with both Boxer and Berdan primers
Ginex doesn't import ammunition. They are best known in America for their Boxer primers
 
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Are metric primers specific to metric calibers? Are both 9mm Makarov and 9mm primers available?

Where dos it say that these are metric?
The 9mm Makarov primers in reloadable brass that I have see are boxer primers.

Every now and then I will run across reloading information talking about metric primers. I am trying to figure out if there is any difference between metric and standard primers.

Maybe he is talking about Mecuric Primers containing fulminate of mercury release metallic mercury which is destructive to brass.
 
The OP probably got the "metric" from threads like this one:

"So I immediately busted out my calipers and checked the seating depth...because metric primers are often not seated deep enough. I thought, you know....this would be a good time to take some pictures in case there are folks out there who don't know how to measure primer depth."



I have been using Wolf primers from back when they were made in Russia. As to size there is no difference. They may be a little "harder" than others but you seat them like any other!

There are no "metric" primers, it's a new buzz word!

I have LP. SP, LR and SR, never measured a single one.
 
Metric primers are a generic term for primers that are produced in metric countries and the specifications are written around the metric systems. They are about a thousandths bigger in diameter, maybe 2 thousandths taller. As Geodude alluded, this is probably due to their specs and standards and inspections being based on metric, and ours on SAE...so there is a tiny disparity on the conversion. In addition, many of them are military spec primers or designed for the guns predominantly popular in those countries, so may have shorter or harder anvils, harder cups, or other variances. Most of them are harder to seat than US primers, leading to a prevalence of negative opinions about them. The difference is very negligible, but is enough that in some applications, with some brass, and some priming systems they can be a real pain. The main pro is that they are cheaper, and more easily available. They work fine as long as you go into it knowing they take more work. If you want the easy button, stick with US primers. Pics below to demonstrate the difference, top is Ginex, made in Bosnia. Bottom is US made Federal. Both Large Rifle, the Fed is LR Magnum. I just happend to have these out because I'm loading with both for two different applications. Note, it's pretty hard to measure these...you put to much pressure and they start to deform...to little and the reading is not accurate. I've measured a bunch of them, and get an average of 1/1000's of difference, little more in height. I've taken them apart and the ginex cup itself is super soft, softer than fed...but the anvil is much much harder than fed. I've not taken apart and played with any other metric primer, so can't speak to their construction.

TLDR; They work fine, just know it will take more effort.


ginex.jpg


fed.jpg
 
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oh good. I'm not the only one with that problem. I thought I was crazy. you can get all 100 if you pull the end pickup cap out a bit.
Or switch to the the brass tips...but then you get the "one hangs when dumping in the priming tube", so I use my primer follower to rod the pickup tube through. Then as well, small primers stack up at the gate in auto priming systems like the Mark 7 revo...so you have to watch that. I made a special tool....a straightened paperclip with a tiny hook on the end for reaching in and hooking the hanger, lol.
 
When I was working in aerospace - early ‘80’s thru mid ‘90’s - the emergence of PC’s which were both more nearly affordable and simpler to operate than Unix workstations to calculate to the seventh digit and round to the third was both a boon and a curse. Piper and MacDac were/are multinationals so we made parts in both units for different contracts all on the same production floor. Which is how I ended up with duplicate tools in SAE and SI. 😖
 
I think the problem is with the end user, not the part, but that’s just me. I’m pretty flexible.

That's way they see it. Their stuff, fits their stuff, they consider the job complete upon firing, after ejection, they don't care much about what happens.

Same could be said of aluminum/steel and stepped brass, in that respect.
 
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