Adjustable gas plug

[Anvils]

I sure thank all of you for the great information based on your actual experiences! I have loaded ammunition for FAL and AR-15 for years with standard LR primers and never had any problems but after buying a Garand I started reading all about slamfire problems. I am glad I have now got first hand knowledge and I can load some ammo and get to the range.
Thanks again, Norm

[rider]

Thank you! I found a small amount of 4895 today so I will use that with my regular cylinder plug. I can't find the CCI #34 primers but I do have CCI and Winchester large rifle primers. Can I use them and be reasonably safe? Some info I have read warns of slam fires but several Garand shooters at the range are using regular large rifle primers ???????
I have reloaded for years for my bolt and lever rifles and didn't realize the Garand ammunition was so specialized. Never too old to learn!

Norm

Widener's has IMR-4064 and British surplus 4895 in 8lb kegs. They also have H-4895 and Vitavuori N-140 in 1lb cans if cost is no object.

[jim r]

One of the primary causes of a Garand slam fire is failure to inspect the firing pin leg and the safety notch in the belly band that runs under the rear of the bolt when in battery, most often it is not a soft or high primer. Years ago I had a Garand come into the shop that would at random slam fire. I installed a new firing pin as the original had a very badly worn leg. The safety notch was also worn. I sent a paper photo to Clint Fowler for his opinion to see if it need to be re-welded and the receiver then re-tempered. He seconded my opinion that the notch was still serviceable. The new firing pin solved the problem. Special primers are not needed just inspect your firing pin leg and keep a new spare handy.

THIS IS GOOD INFO HERE, but sloppy primer seating will cause a slam fire

[slamfire1]

I was worried about Federal primers, but now I am glad to find out that the posts I read about sensitive primers and slamfires are all wrong. The shame of it is , there are these delusional guys who keep posting these slamfire experiences that could not have happened.

Maybe you smart guys ought to get into these threads and tell them they are nuts.

"http://m14tfl.com/upload/showthread.php?p=411860#post411860"

M-14 Firing Line Public Forum

01-07-2009, 04:55 PM
SGT D USMC FNG Join Date: Dec 2008Location: oregonPosts: 13

I had a slam fire in a M1. feel free to disreguard this post because few shooters have first hand knowledge, and even fewer have had one. It only happens to others so why worry, except if you are using federal match (very accrate) primers in a gas gun, You are playing russian roulette. My slam fire was in the mid 1980's. It was with a Federal match primer. I got very involved in this and found 17 cases of M1 slam fires with one common factor, ALL WERE WITH FEDERAL MATCH PRIMERS.

"http://www.usrifleteams.com/forums/index.php?showtopic=4824&st=15"

John,

Congrats on your great performance at Perry.

I had to vote "Other". I have just scanned all the posts on this thread so far, but did not see any comment about the primers I use, which are the CCI Mil-Spec primers. I use the CCI 41 in the 223 that I shoot in my AR-15 Space gun (the Space Beast) and the CCI 34 in my 6.5 CHiP wildcat that I shoot in my AR-10 (the Space Monster).

These primers were designed to require 50% more energy to set them off in the standard drop test. To give them this "toughness", they have a slightly thicker cup and a slightly different anvil geometry than regular CCI primers. I was also told by Alan Jones of CCI that the amount and type of priming compound used in them is the same as what is in their magnum primers of the same size, making the CCI 34 and 41 equivalent to the CCI 450 and 250 respectively

I use these primers for one reason: SLAMFIRE PREVENTION!

I have had one slamfire in my shootng career. It happened back in 1990 when I was shooting an M14/M1A and that experience was the basis for the first article I ever wrote for Precision Shooting. Back then, the CCI Mil-Spec primers were not yet available; and after some testing, I switched from using the Federal 210Ms to the Winchester WLR. I have never had another slamfire after that first one, but it was enough. I hung up the M1A in 1993 after legging out and went back to the bolt gun, but when I began playing with the AR-15 Space gun that I call the Space Beast, I immediately started to use the CCI 41s in the ammo for it.

There was a time when these primers were hard to find, I think because of military orders; but now they seem to be more available. I got my most recent batch from Graf & Sons of Mexico, Missouri.

I do use one other primer in my 6.5 CHiP (which is the short 6.5-08 I chambered my AR-10 for), the CCI BR-2, but only for my 600 yard load with the 142 grain SMK. I picked this primer for this load only because loads with it gave me slightly better accuracy than the same loads with the CCI 34 in early testing, and I didn't want to use up a lot of barrel life trying to find a load that would give me slightly smaller groups when I was already getting slightly under 0.5 MoA at 200 yards. At 600 yards, I only shoot these single-loaded. They are never fed from the magazine because I don't like to have the bullets possibly be knocked out of alignment by being bashed into the feed ramps on their way into the chamber.

Just some things to think about.

All the best, Randolph

"http://www.thehighroad.org/showthread.php?t=467078&highlight=federal"

Mine was once more than nine years ago and it rattled my faith in the old girl for sure - I mean it's a GARAND!

It was the first round of a full clip and the rifle closed all the way (as far as I could tell) so the only damage was to my trust in things. The round went downrange safely - even hit my target backer although I hadn't set into aiming the shot. It fed the next round just fine which was also Federal primed and didn't fire that one. I unloaded the rifle.

I set that rifle aside for the day as I wasn't sure what had happened. Another shooter asked me about the primer used and told me for the first time I'd heard it that Federal primers were too sensitive to use in semi-auto rifles. I didn't know any better and still am not sure of it but I've never had one slamfire using Winchester or CCI priming. I know that one incident isn't enough to substantiate a blanket condemnation but seeing you say it struck home for me.

There didn't seem to be anything wrong with the rifle and that's been proved out over a couple thousand rounds since, so I've taken it on faith and not used a Federal primer in any of my Garand rifles since.

It's a Springfield Armory, 1-55 date barrel but it isn't original to the receiver, though it came from CMP on another receiver that I converted to 7.62. It measures like a new one and has three "P" stamps, one "T" stamp, the small "m" and "A217B" on it. A couple of people have thought that it was a barrel designated for NM use, but I don't know any of that. It IS a good shooting barrel though.

I only know that nothing about the barrel or the receiver (so far as I can tell)contributed to that slamfire episode. To play it safe I took a little cut to take the headspace out to just short of my "No-Go" gauge because it had felt a little resistant closing on my 'Go' gauge and I thought maybe that could have brought the slamfire. It was probably just my worrying.

I use an old set of RCBS dies, hand prime with a Lee Auto-prime (or whatever it's called) to be sure of my primer set. The round was good but it had Federal No.210 priming and not being able to find another reason for that slamfire I switched to Winchester primers for the rest of my loading for the caliber.
It's been a lot of years since I shot high power matches so now I'm content to shoot CMP ammo, the Greek stuff these days

[John Kepler]

Glad you've FINALLY seen the light!

I have someone you need to talk to. The man is Mark Kovac and he's the retired Chief Armorer of the DCM/CMP. Back in the day, Mark was responsible for all those thousands of M1's and M14's in the hands of State Associations et.al. It was his job to examine and repair the rifles after what were being called "slam-fires". In over 30 years doing that, you know how many slam-fires he and his team finally attributed to "soft primers"? Not a single one! And believe me.....if Mark had found a link between a specific primer and the mountain of work rifle problems created for the DCM....he would have "sent the memo"!

In every case where it was conclusively a slam-fire, the rifle was busted! Generally with a worn firing pin, worn bolt, or (in the case of SA cast-receivered rifles) a mis-location of the firing pin retractor bridge. Remember gang....identifying a worn firing pin isn't a "Mk.I Eyeball" job! If the firing pin extension is worn by only a few thou, your slam-fire risk has risen exponentially.

The other cause, as was well-documented in an American Rifleman article I read probably 25-30 years ago, are primer seating defects...a high primer, regardless of who makes it, is a slam-fire risk! The author of the article discovered that little factoid the hard way, and researched and wrote the article as a result. His well-researched article should have put the "soft-primer" myth to bed for good....the data was that compelling, but obviously not.

I know how you feel about this subject, I know how much a prisoner you are of your own experience, I know how thoroughly convinced you are that it's always the primer's fault to the exclusion of any and all other viable explanations so any discussion of the topic will be a complete waste of time. But science and engineering says you look at the data...ALL of the data, not just some of it, not just the data that agrees with your preconception/theory. That examination says that actual slam-fires are exceedingly rare, that several other factors have to be involved, and statistically, no one primer-type is involved more often than another. Data, not anecdote!

[slamfire1]

I have someone you need to talk to. The man is Mark Kovac and he's the retired Chief Armorer of the DCM/CMP. Back in the day, Mark was responsible for all those thousands of M1's and M14's in the hands of State Associations et.al. It was his job to examine and repair the rifles after what were being called "slam-fires". In over 30 years doing that, you know how many slam-fires he and his team finally attributed to "soft primers"? Not a single one! And believe me.....if Mark had found a link between a specific primer and the mountain of work rifle problems created for the DCM....he would have "sent the memo"!

That would be interesting, to find out how many DCM rifles slamfired and if there were any failure report data. But as it is, this guy himself is not providing information that can be examined. As for not attributing a single slamfire to an overly sensitive primer, if he was not looking for it, he would not have found it. Instead he would have found a different, rational cause, and would have been wrong about it.

Before people knew about ergot poisoning, they ascribed the subsequent food borne symptoms to demons and witches. People were hung as witches. They were tested, and the testing evidence was examined in court. Just read about the tests used in Salem to prove witchcraft. Rational people who came up with rational tests that proved witchcraft. And they were wrong. I don’t see any difference with your expert. He must have discounted or ignored anything about primer sensitivity to come to a conclusion like that.

The other cause, as was well-documented in an American Rifleman article I read probably 25-30 years ago, are primer seating defects...a high primer, regardless of who makes it, is a slam-fire risk! The author of the article discovered that little factoid the hard way, and researched and wrote the article as a result. His well-researched article should have put the "soft-primer" myth to bed for good....the data was that compelling, but obviously not.

I find nothing in Mr Faatz article to support the idea that “soft primers” are a myth. For the record, his article was "The Mysterious Slam Fire", 'American Rifleman' 1983.

Mr Faatz had a slamfire in a Garand. What Mr. Faatz did show is that you can ignite a high primer in a Garand, but it took him a lot of time and jiggling to do so. And he added to our knowledge and hats off to him.

If you recall from his article, the first thing on his list of slamfire contributors is sensitive primers. A subset under sensitive primers is high primers.


His list was

1. Sensitive Primer (included under this category is a high primer)
2. Minimum headspace chamber and inadequate case sizing (leading to the firing pin hitting the primer with excessive force)
3. Hammer following the bolt
4. Fouled bolt face

He could have added busted firing pin.

The FAL Files Forums - MY FAL KB UPDATED)

Also check the editor’s notes in the article where the NRA staff had three slamfires out of 100 rounds in a M1a. Noted in italics is the statement “Commercial primers are somewhat more sensitive than military primers”

In every case where it was conclusively a slam-fire, the rifle was busted! Generally with a worn firing pin, worn bolt, or (in the case of SA cast-receivered rifles) a mis-location of the firing pin retractor bridge. Remember gang....identifying a worn firing pin isn't a "Mk.I Eyeball" job! If the firing pin extension is worn by only a few thou, your slam-fire risk has risen exponentially

Mark Kovac's universe must limited to only one type of rifle. There is more than one semiautomatic mechanism in the world. Slamfires are not the exclusive domain of M1/M1a’s. It does not take much effort to find accounts of slamfires with SKS”s, MAS 49-56 rifles, AK’s. If you are not familiar with these rifles, they have free floating firing pins. A few slamfires have been reported with FAL’s and that rifle has a spring loaded firing pin.

THR - View Single Post - FAL Explosion

These people would disagree with you about the myth of the “soft primer”. After reading this thread it is evident they are familiar with slamfires in AK’s.

AK slam fire question - XDTalk Forums - Your HS2000/SA-XD Information Source!

Notice that the poster examined his AK for hammer following, tested it five days later with different factory ammo, and did not have any slamfires.

Seems the ATF has proved that some primers are more sensitive than others. A mechanical problem and sensitive primers could land you in jail with the ATF!

FAL doubling leading to ATF seizure.
The FAL Files Forums

The rifle in question never doubled on me and I shot it in numerous matches.

The atf got it to double by putting the selector on FA and trying many different types of ammo until they found one with a super soft primer that would double when the hammer followed the bolt home

At the actual test firing that we conducted there were 12 tests with 4 types of ammo and only the Winchester hunting 308 doubled and it did it only twice.

The problem was a worn out firing pin spring.

I know how much a prisoner you are of your own experience, I know how thoroughly convinced you are that it's always the primer's fault to the exclusion of any and all other viable explanations so any discussion of the topic will be a complete waste of time. But science and engineering says you look at the data...ALL of the data, not just some of it, not just the data that agrees with your preconception/theory. That examination says that actual slam-fires are exceedingly rare, that several other factors have to be involved,

Maybe I have over emphasized primer sensitivity as a cause. Hammer follow through and busted firing pins have certainly caused a lot of slamfires. However the main point you have made in this thread seems to be that primer sensitivity is the same for all primers and that is wrong.

[AKA Hugh Uno]

**************
Seems the ATF has proved that some primers are more sensitive than others. A mechanical problem and sensitive primers could land you in jail with the ATF!

FAL doubling leading to ATF seizure.
The FAL Files Forums

************

I have never heard of this alleged ATF primer "experimentation" of FAL lowers??

Feel free to give us actual verifiable information instead of a dead-link to fal-land.

The FAL "machine gun" part is the UPPPER. You cannot buy ANY true FAL upper (except a few legal CLass III items).

[slamfire1]

Feel free to give us actual verifiable information instead of a dead-link to fal-land

Feel free to look.

Or do you need to be spoon fed everything?

Try going to Google, go advanced search, "ATF doubling"

site:FNFAL.com / The FAL Files

The FAL "machine gun" part is the UPPPER. You cannot buy ANY true FAL upper (except a few legal CLass III items).

Do you know which of these parts will really get you into trouble?

[AKA Hugh Uno]

"gun show waiting line experts" often post to things that may or may not actually exist (e.g. the recent "DOD advisory message on dangerous/bad Wolf ammo' bogus information that three different people "swore" was not bogus and that they saw it personally).

Since you can't seem to produce a valid link, I will have to assume it's probably not valid info.

you can keep your spoon.

[slamfire1]

The FAL Files Forums - moses ATF ordeal

Need a pacifier too?