Which commercial primer is the "hardest?"


March 5, 2006, 02:03 PM
Which commercial primer is the "hardest?"

I recently read you need “tougher” or “harder” primers when reloading for an autoloader—in this case an M1A.

The reason, of course, is that many commercial primers are “soft” and the chance for an "out of battery firing" is increased with a “soft” primer.

So, which primer is considered the hardest? CCI, Federal, et cetra.

Thanks so much for your help!

If you enjoyed reading about "Which commercial primer is the "hardest?"" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!
March 5, 2006, 02:28 PM
Military primers. CCI makes them. They are maybe $1 more per 1000 than civy primers (at least on line).

March 5, 2006, 03:07 PM
From what I understand CCI and Winchester primers are hard enough for this application. Federal has a reputation for being too soft.

For what it's worth, I use CCI BR2s in my M1A and do not have a problem. I am very careful about getting the primers seated below flush in the pocket - I use Sinclair's primer pocket uniformer to make sure the pocket is deep enough, and I check every round before I box it up.

You might be interested in this article on reloading for a match M1A: http://www.zediker.com/downloads/14_loading.pdf

The Bushmaster
March 5, 2006, 04:39 PM
According to the primer people they buy the cups from the same supplier...With that said...CCI seems to have the hardest or require the stronger hammer strick to set them off. Winchester is one of the lightest to set off. At least that's what I have found while piddlin' around with them. I use both CCI and Winchester although I have gone more to Winchester. I still use CCI in my Mod 94 as it gives me the best down range preformance...

Peter M. Eick
March 5, 2006, 07:46 PM
CCI C-34's. Specifically made for the hardness.

NOTE these are magnum primers. Adjust your loads down if you are using a book that is not listing a magnum primer for your particular load.

March 6, 2006, 01:23 AM
CCI's are the hardest. Some guns have problems with them because they are simply too hard.

March 6, 2006, 09:19 AM
CCI the hardest, Federal the softest. I've got a couple of guns with light springs that will only shoot federals reliably. I've got one gun that won't fire any cartridge with a CCI primer.

March 6, 2006, 11:18 AM
I've shot several thousand WLR primers through the M1A and have had no issue. Nobody locally carries the #34 primers.

Paul "Fitz" Jones
March 8, 2006, 09:48 PM
The only primers I will consider using during my long career are Federal and Winchester and Winchester are the hardest.

March 8, 2006, 11:22 PM
Yeah, I understood that the primer CUPS are pretty much the same, but that the SENSITIVITIES are different. Probably has to do with the exact component mix in the pellet, anvil placement, etc. I haven't had any problems even with Federal in an AR, but have heard of some difficulties.

March 10, 2006, 01:22 AM
Randy Ketchum of Lynwood guns tells me that all primers have the same hardness of brass, but they vary in thickness


Rifle primers vary from .019" to .027" thick:

March 11, 2006, 01:03 PM
Military primers should be the hardest to set off because they are designed to minimize "slam fires." I load on a Dillon Press. Dillon (and probably most of the other progressive manufacturers) recommend only CCI and Winchester. I've used Remington primers on my Dillon when I got a righteous deal on a case of primers. Price aside, I follow the recommendations from the professionals. They have the most experience. :D

March 12, 2006, 11:12 PM
I'd agree with the Military answer. Also, FYI from years of gun magazine reading:

"CCI pistol primers are generally assumed to have a slightly thicker cup. Federal primers use a thinner cup than CCI, Winchester and Remington, so Federals can ignite with a lighter blow.

Remington 7½ primers have a thick, soft cup (some say just harder) which makes them easier to light but also very tough. They should eliminate any problem from the cup flowing into the firing pin hole. Remington 7½ Benchrest primers have the thickest cup. The Federal 205M is equal to the Remington 7½.

Most small pistol primers, standard and magnum, have a cup thickness of .015-.020”, but each is annealed and hardened to different specifications. Standard Federal 100 and CCI 500 primers generally give good results with loads up to 35,000 psi, and have great sensitivity. Winchester Small Pistol Magnum and Remington 5½ will give good service against primer flow."

March 13, 2006, 01:35 AM
From what I've read, the biggest factor is how sensitive the priming compound is.

shooting time
March 14, 2006, 08:57 AM
From my experiance CCI is the hardest I quit using them and switched to Winchester the softest

March 14, 2006, 09:00 AM
I have used CCI in my Mini-14, AR15 and M1A for over 20 years. Never had a primer ignition problem. I have sometimes used Federal, Remington & Winchester and never had a problem either.

If you enjoyed reading about "Which commercial primer is the "hardest?"" here in TheHighRoad.org archive, you'll LOVE our community. Come join TheHighRoad.org today for the full version!