Primers for Military Arms

[3/2ACR Vet]

Okay,
I've almost got everything I need to get started loading.

I've run into a bit of uncertainty on primers for the ammunition I'll be making.

I'm loading .308 for an M1A, and .223 for an M4 variant (that can handle 5.56). Last weekend I went on a field trip and was able to obtain several good powders.

The sticking point is primers.

I could have had a brick of Large Rifle, but when I mentioned that I was loading for an M1A, several people cautioned me not to use the CCI large rifle, to avoid a slam fire situation.

Since then, I've done a lot of reading. I already knew about slam fire phenomenon, from past experience with shooting in the military. It was discussed as something that rarely happens, and I also knew that the M1-M14 style rifle can have this happen, because the firing pin floats.

Unfortunately, all my reading only served to confuse me a bit. About half the things I read (including the "loading for M1" stuff from other threads here) didn't mention needing any special primer, or to do anything other than ensure the primer is set flush or slightly low in the primer pocket. Others maintain that a military grade primer like the CCI #34 is the only thing you should use.

I'm hoping some of you have insight or experience in this. Should I get the opportunity to get hold of regular large and small rifle primers, are these safe to use (I understand the AR platform can slam-fire as well), or should I be patient and wait for the boxes of #34 and #41 primers I've waitlisted several places?

 

[DaemonAssassin]

Okay,
I've almost got everything I need to get started loading.

I've run into a bit of uncertainty on primers for the ammunition I'll be making.

I'm loading .308 for an M1A, and .223 for an M4 variant (that can handle 5.56). Last weekend I went on a field trip and was able to obtain several good powders.

The sticking point is primers.

I could have had a brick of Large Rifle, but when I mentioned that I was loading for an M1A, several people cautioned me not to use the CCI large rifle, to avoid a slam fire situation.

Since then, I've done a lot of reading. I already knew about slam fire phenomenon, from past experience with shooting in the military. It was discussed as something that rarely happens, and I also knew that the M1-M14 style rifle can have this happen, because the firing pin floats.

Unfortunately, all my reading only served to confuse me a bit. About half the things I read (including the "loading for M1" stuff from other threads here) didn't mention needing any special primer, or to do anything other than ensure the primer is set flush or slightly low in the primer pocket. Others maintain that a military grade primer like the CCI #34 is the only thing you should use.

I'm hoping some of you have insight or experience in this. Should I get the opportunity to get hold of regular large and small rifle primers, are these safe to use (I understand the AR platform can slam-fire as well), or should I be patient and wait for the boxes of #34 and #41 primers I've waitlisted several places?

For the .308, use the CCI 200 primers. I've never had an issue in a RRA LAR-8, or any other rifle (semi and bolt) I have run my CCI 200 .308 loads through.

What they might be speaking about with the slam fires, is that the primers weren't seated far enough into the primer pocket of the brass.

I also use the CCI SR primers (kinda tired and don't remember the number offhand) when loading .223/5.56 for a M4 civilian clone. I've never had any issues with CCI primers in that rifle either.

CCI primers are some of the best that I have seen/used when it comes to initiating the powder burn. Nothing worse than having that trophy deer (or dinner) in your sights and it just goes click (that happened with Winchester primers). After that I started using CCI's and never had that problem again.

 

[phantom14]

CCI # 34 primer for any self loader with a free-floating firing pin (such as M14-type).

See Faatz: American Rifleman article at:

www.mtssa.org/olofson/slamfire/Mysterious Slam-fire.pdf

 

[byf43]

^^^(Wayne Faatz was a very active member of SCSC in the late '70s-early '80s!!! He was a GREAT asset to the High Power Rifle Program, and was one heck of a nice guy! IF memory serves me, he was an Honorary Life Member.)

http://www.legacy.com/obituaries/indystar/obituary.aspx?pid=160473770#fbLoggedOut



I've used CCI, Winchester and Federal primers in my AR rifles, M1 Garand and my M1A.

Of all of these, the Federal primers REPORTEDLY have the softest cup.
Do they!?!?!?! I have no idea.

I just know that they work for me.

When loading for these rifles (loading everything, actually) I make certain that the primer pocket(s) are CLEAN and that the primers are fully seated.


I've been loading my own ammo since 1979, and loading for Service Rifle type firearms, since 1983.
ZERO issues. . . . sofar.

Watch your reloading practices, and have at it.

 

[blackseven]

I was able to pick up a box of #41 at X-Ring supply before things got crazy. I count myself lucky to have found them. No idea what I'll do when I run out, so I'm certainly paying attention to this thread.

I have Winchester Large Rifle primers for 308, but I use them in a bolt gun, are there problems using them in a semi auto ?

 

[Megiddo]

Finding ANY primers is the problem now.

I hear you on this because I was sold (and didn't know any better) Remington 6.5 primers for my AR. Turns out that was a no-no. I did put a case with a primer together and tested it (without bullet or powder) and there was no bang. But I did see a tiny dent in the primer.

 

[lx1x]

been using regular cci primers for my autoloaders (ar's).. no issues with slamfires..

only read federal primers are much more sensitive with slam fires.. havent used federal primers to find out.

 

[jimbobborg]

I've never had a problem with CCI standard primers and slam fires. I've used them in several AR-15s and a Mini-14.

 

[Winterborn]

Finding ANY primers is the problem now.

I hear you on this because I was sold (and didn't know any better) Remington 6.5 primers for my AR. Turns out that was a no-no. I did put a case with a primer together and tested it (without bullet or powder) and there was no bang. But I did see a tiny dent in the primer.

This isn't uncommon for any type of primer in an AR. The thicker cups on the so called "military primer" prevent going off from this type of impact from the floating firing pin. I would not be concerned too much.

Supposedly (I have no personal experience) Federal primers have a thinner cup and are thus more susceptible to slam fires; YMMV.

 

[coopermania]

Jesus Christ, Use any Large or Small rifle primers you want. Just start your loads where to book tells you and build up from there. Some people here need to step away from the internet.

 

[stu929]

I've only heard of slam fires in very dirty rifles or ones with poorly seated primers.

 

[Pinecone]

CCI #450 Small Rifle Magnum primers have the same cup thickness as the military CCI primers. The military ones have a slightly great distance between the cup and the anvil.

And Remington 7 1/2 primers are supposedly the same primer they load in military 5.56.

 

[phantom14]

Okay. I'm offering up "private stock". Check here:

http://store.thirdgenerationshootingsupply.com/browse.cfm/2,3716.html

Fast service. Reliable.

Hurry. Had over 350 last week. Only a hundred or so left.

(I hate myself. We won't see this again soon.)

 

[Tebonski]

I use military primers for military semi auto rifles. If you choose not to please always keep that muzzle down range when you chamber and fire. Using a softer primers can cause a slam fire. I've seen it with SKS rifles and military ammo.

Better safe than sorry.

 

[FlatsFlite]

Jesus Christ, Use any Large or Small rifle primers you want. Just start your loads where to book tells you and build up from there. Some people here need to step away from the internet.

Plus 1

Primer depth is key. Get it right.

I have yet seen any data on the hardness rating of various primers. Would that be rated on? The mohs scale, Rockwell, Vickers? I dont have a clue, but I've never seen the data on any actual hardness ratings of primers.


However, I have seen cup thickness measurements done. CCI and Wolf have the thicker cups, but we talking about an extremely small amount of difference.

 

[Jerry M]

Plus 1

Primer depth is key. Get it right.

.../QUOTE]

Shot over 3,000 through AR last year including over 2,000 shooting prairie dogs in South Dakota. Previously I have shot thousands through a AR10 and M1-A. Used regular primers all!

Good luck

Jerry