Garand Slam Fire

[GASCHECK]

Shooters:
I came across a thread that discussed using mil primers to prevent slam fires with the Garand. I'm not at all sure, and am too lazy to get the TM, but isn't the firing pin held back mechanically until the bolt is closed?:confused:
Gascheck

[Darren007]

True but they can stick out just far enough that with the force of the bolt, can set them off. Not sure about Garands, but for example if you look at an SKS. You can see just a "nub" of the firing pin protruding through the hole.

[Buzzcook]

I haven't heard of that problem with a Garand.
I'd guess that avoiding soft primers would be a good idea just in case.

[Hommbs]

The firing pins in the Garand, M14/M1a, and the m16/AR15 are all free floating. Even upon chambering of a cartridge in these weapons you will get a bit of a dimple on the primer from the firing pin as it slides forward and contacts the primer. It's normal on these weapons.

[T. O'Heir]

Slam fires in any semi-auto rifle are caused by improperly loaded ammo. Usually high primers.
CCI "milspec" #34 primers are a marketing gimmick. They're just magnum rifle primers. No .30-06 powder requires magnum primers. Magnum primers burn a bit hotter for a bit longer and are made to ignite hard to light powders and for cold weather shooting. Otherwise, regular large rifle primers, seated properly, will be fine. The make of said primers doesn't matter.
The TM says nothing about the primers or the ammo. However, it's handy. It's about maintaining the rifle. Tells you where to grease.
Go here for a free .pdf M1 Rifle TM and FM. Note the need for the provided UN & PW.
http://www.biggerhammer.net/manuals/
And the rifle was designed to use .30 M1 ammo with its 174.5 grain bullet at 2640fps, not .30 M2 ammo with its 152 grain bullet at 2800fps(after 1940).

[Tim R]

I agree 100% with T. O'Heir. I would not recommend using Federal primers in any rifle with a free floating firing pin how ever. Plain ole' CCI and Remingtons work very well. I like the "Bench Rest" or match primers my self.

[Chris_B]

It's also possible to 'bump fire' these weapons. Saw a video and I don't recommend it both for the barrel wear and the spray of lead

But I personally have fired two shots on a properly working M1 ('44) while in the seated position, while pulling the trigger once. The ammo was USGI M2 Ball, Lake City '42. The event happened last summer. Eight rounds, seven trigger pulls. I can't have bump-fired it, I don't see how I'm strong enough especially while seated. Perhaps that round was poorly loaded back in '42, I don't know and I'm not a forensics guy but I know what happened. The worst part was there were only 7 holes on the target ;) I will say that the ammo could be suspect, I had a ruptured case on a round from that same lot while firing an M1903A3. We pulled the bullets we still had from the cases at that point. The M1903 is a nice strong rifle and nothing bad happened to me except a little black spot on my cheek, and I was wearing safety glasses

[Tim R]

Chris, it was not the ammo which you got the double from. It was because you where "milking the trigger". Quit trying to shoot it like it was a pistol :) as this sets it up for a bump fire if you will.

I've had 2 rounds and the empty clip come out all at once. It comes from gently pulling the trigger on the second stage.

[Swampy1]

But I personally have fired two shots on a properly working M1 ('44) while in the seated position, while pulling the trigger once. The ammo was USGI M2 Ball, Lake City '42. The event happened last summer. Eight rounds, seven trigger pulls. I can't have bump-fired it, I don't see how I'm strong enough especially while seated.

I agreee with TimR 100%....

Chris,

You experienced a "double" fire. Very common in the M1-M14 family when being fired from a bench by someone not familiar with the vagaries of the types trigger.

The rifle functioned completely normal. It fired twice because the trigger was pulled twice..... You just did it so quickly that you didn't realize it. You effectively "bump" fired the rifle without knowing it.

When firing an M1 or M14 from a bench you MUST keep FIRM back pressure on the buttstock with your firing hand to pull the buttstock into your shoulder. This prevents the rifle from recoiling, bouncing off your shoulder and impacting your trigger finger for a second shot. It also helps to do a full follow through on the trigger.....

As I said... this is very common when shooting from a bench. If you get doubles from field positions (i.e. prone, sitting, kneeling, or standing.) where the rifle is fully supported by the body and is naturally held into the shoulder tight enough to prevent them..... then you may have issues with worn or out of spec trigger group components. Have a competent M1 mechanic check out the trigger group.

Best regards,
Swampy

Garands forever

[AK103K]

If you shoot a Garand or M1A/M14, and plan on reloading for them, regardless what primers you use, I would suggest that you get a primer gage that checks seating depth, especially if you use military brass that has or had a crimp. I would also recommend using commercial brass. Its a lot easier to work with and you will get more loads out of it. It probably wouldnt hurt to get a case gage too, just to make sure your dies are set right.

These rifles have a slotted bridge in the receiver that is supposed to keep the firing pin cammed to the rear of the bolt until the bolt locks up. You will still get small firing pin indents in rounds that were loaded into the chamber though. Is that enough to set off a sensitive primer? Whos to say. Then again, if harder primers are available and work just as well, why not use them.

Slam fires in any semi-auto rifle are caused by improperly loaded ammo.
I'm sure this is one cause, but not necessarily the only cause. A broken firing pin can also be an issue and who knows what else.

My Garand went grenade while shooting DCM issue factory LC 69 ball. It was never determined why it cut loose. (gun was returned to the DCM) The rear half of the case that blew the gun was recovered, as were a couple of cases with the necks blown out that were fired during a rapid fire string. The gun did "double" a couple of times on me during that string too, which I thought was a little strange at the time, as I normally dont have that kind of problem, and probably should have paid closer attention as it was a new (to me) gun. My fault there. If I had recovered the brass before starting the slow fire string, I may not have continued, but, who knows and it doesnt matter now. The primers on all three cases appeared to be OK. Most all of us were shooting from the same lot of ammo. No one else had any issues.

If you shoot a Garand and load single rounds, get a SLED. Dont single load by inserting a round in the chamber and letting the bolt fly. If you shoot an M1A, push the round into the top of the mag first.

Pay very close attention to your reloads and your loading practices. I will not shoot anyone elses reloads. While I still shoot M1's and M1A's, I've become very picky about what I shoot in them and how I shoot them.

[GASCHECK]

T. O'Heir:

I was going to refer to the TM to find out about the firing pin being restrained, not for primer info.

"And the rifle was designed to use .30 M1 ammo with its 174.5 grain bullet at 2640fps, not .30 M2 ammo with its 152 grain bullet at 2800fps(after 1940)."

Does that mean all the ammo used after 1940 is incorrect? Stop confusing an old man! :D I got 3,125 IMI 152 grain FMJ bullets downstairs.

I don't load much for the Garand anymore as I have lots of Greek and Danish stuff.

How about single loading by inserting a round and easing the bolt shut?


Gascheck

[T. O'Heir]

"...ammo used after 1940..." Early M2 ammo velocity was 2700fps. In 1940, the muzzle velocity was raised to 2800fps to match the ballistics of .30 AP ammo and its 168 grain bullet.

[Gbro]

Slam fires in any semi-auto rifle are caused by improperly loaded ammo.

I witnessed a slam fire with a Rem742.
nephew was loading rifle and it discharged when the bolt was released.
It went to the Gun Smith the next day.
The cartridges(factory Rem Corelok) in the magazine showed small dead center dimples in the primers.
The Rifle was found to be missing the firing pin return spring. That bolt had never been removed from that rifle.
Rifle was pointed in a safe direction, A real eye opener.

[Gewehr98]

The Garand was designed to load ammunition from the magazine, which slows down the bolt and subsequently the free-floating firing pin.

If you don't use CCI #34 (milspec hard) primers, and simply drop the bolt on a chambered round, you will see a dimple in the primer. Been there, done that, and have seen it myself with many, many M1 Garands while I coached John C. Garand Match shooting clinics.

High-seated primers are one cause of slamfires. Soft primers and non-use of a SLED when chambering single rounds are another potential for disaster. When an M1 Garand is within blueprint tolerances, the bridge in the receiver designed to hold the firing pin tail works like it's supposed to, preventing firing pin protrusion until the bolt is fully locked.

Unfortunately, thanks to 50+ years of soldiering on, not all M1 Garands are still within blueprint tolerances, and may not have been when they left Springfield, Winchester, H&R, and International Harvester originally.

I've seen too many firing pin dimples in M1 Garands to not use a SLED and CCI #34 primers these days.

It's not a new TFL thread topic, by any means:

http://www.thefiringline.com/forums/showthread.php?t=214081

[GASCHECK]

Seems I just can't get an answer. :(
How about inserting a round in the chamber and easing the bolt shut????

Gascheck

[AK103K]

Easing the bolt shut is a lot better than letting it slam home on a loose round. I dont think its a problem, but it just takes a little more attention when your lowering and seating the bolt.

The SLED allows a single round to be loaded as its supposed to be. They are cheap and readily available and take away most of the risk.

[MythBuster]

"Seems I just can't get an answer.
How about inserting a round in the chamber and easing the bolt shut????"

That will work just fine.

[Tim R]

Gewehr98, I've seen every primer "dimpled" on every round chambered by a M-1/M-14/M-1A, not fired and then removed no matter what primer was being used.....GI ball included. Even my tuned 308 M-1 which had the firing pin sprung dimples the primer.

My AR dimples the primers. For loading 1 at a time, I use a SLED in everything, except the M-14/M-1A. I use a mag with those.

I uniform and swage every case used in my service rifles except the 308 when using M-852 brass. I don't reload the 308 brass more than 3 times for use in my 308 M-1. I use Remington and CCI brench rest primers.

In case anyone reading this dosent understand what we mean by "dimple," this is a small mark left in the center of the primer from a very light firing pin strike from the firing pin when the bolt closes at speed. Normally this is not enough to even think the primer is going to go off. It's a mark not a dent and no where near the same type of mark/dent left by a light strike on a primer by a revolver with hard primer cups. The dimple is normal for free floating firig pins which auto loading and simi auto US service rifles have done since 1936.

[GASCHECK]

Garand Guys:

Well, I must admit I never heard of a SLED and I have had my Garand for 45 years. I have used 5 shot clips. I assume it is a "one shot" clip?
I never seen one in Shotgun News or any other publication. Who has them?
And thanks to all for the info! :)

BTW, my rifle was built by a National Guard full time armorer. He worked on guns from .45's to tank cannon. I bought a receiver and wood and he put it together with a NM barrel, sights and all milled parts. I got a beautifuly figured stock, as he used to just switch them out until he got great wood. Things like that just don't come along any more. :(
GASCHECK

[AK103K]

Fulton armory has them.

They look like this...

http://www.fulton-armory.com/SLED.jpg

It stays in the gun after extraction.

http://www.fulton-armory.com/

Look under M1 parts, accessories. Its about halfway down the page. Clik the link under the pic, they have an explanation of their use.

[dmazur]

There's also an aluminum block version, with what looks like a steel insert at the wear point. It also remains in the rifle after extraction, and locks the bolt back. You have to push down on the round & block to release the bolt, then do the normal "get your thumb out of the way" maneuver...

[Tim R]

When using a sled made out of a clip you lock the sled in place by pushing it all the way down. Then you put the single round in the sled like putting a round in a M-14 mag. You then pull the op rod handle and it feeds the round just like a M-14. The sled remains in place until you remove it. I use the pen I'm using to record data in my data book, tweak the tab which holds the sled in place and pull it out. You will get no damage to thumbs.

[Slamfire]

There is so much information out on the web about slamfires in Garands, I am surprised by the overall reaction, basic denial, and incorrect attribution of causes. The primary cause of slamfires is primer sensitivity. Slamfires happen most frequently in systems with free floating firing pins. I do believe that high primers will cause slamfires.


Mechanical malfunctions, out of tolerance firearms, and shooter created situations happen more frequently than the pure free floating firing pin initated event. Most of those have already been listed by others. However, it is a mistake to attribute all doubling/ out of battery firing, to milking the trigger, hammer following, or high primers. Some of those are undoubtedly slamfires by overly sensitive primers.

To reduce the risk of slamfires to a very small level, you need to add several reloading practices when reloading for semi autos.

1. Ream primer pockets to depth

2. Buy a Wilson type cartridge headspace gage, and size all cases to gage minium.

3. Size cases with a small base die.

4. Seat primers by hand and inspect that all are below the case head.

5. Use an insensitive primer. I do not recommend the use of Federal primers. Federal primers are too sensitive. CCI is the only manufacturer who claims to make a less sensitive military primer. That’s what I use.


I have talked to a number of gentleman who had slamfires with their reloads in Garands and one in a M1a. The one common thread was Federal primers. The old WLR was a great primer, but it has been redesigned to make it more sensitive, and that is not a good thing.

Here are some threads on slamfires with new military ammunition. Slamfires are real, they happen, and they have happened with military ammunition.

http://www.thehighroad.org/showthread.php?t=264020


“While the M1 and M14/M1A do have the "web", slam fires are still possible and can be catastrophic. I was lucky enough to come through one with a GI Springfield M1 from the DCM about 20 years ago using LC 69 issue ammo. The rifle held together for the most part, but did fire out of battery on loading a single round in slow fire. If it had been in a rapid fire string, I most likely would not be typing this right now. The rear of the receiver from just aft of the serial number was blown off and the stock cracked with a big chunk blown out of it. The bolt was jammed into the back of the receiver and would not come forward. The op rod handle ripped the palm of my hand open, and you could read the head stamp of the case in reverse on my palm. The recovered empty case was about an inch long. Never did find the rear of the receiver. The DCM took the rifle back and never did tell me what they determined went wrong. They replaced it with a brand new, and I mean, brand new, never issued H&R.

If you shoot either the M1 or M14, I would highly suggest you either use a SLED with the M1 or load single rounds from the mag on the M1A. Reloads should use the harder primers, like CCI, and I check mine with a seating gage. ”



http://forums.accuratereloading.com/eve/forums?a=tpc&s=518103&f=2511043&m=348101466&r=615101566

“In the summer of 1968 or 69 the Atlantic Fleet Rifle Matches were plagued with slamfires using .308 Match ammo. Seems a terrible long time ago, and I still get upset about it because I lost my best and only chance to leg out on that cartridge. I was in the first relay at 500 yards (not 600 because the Annapolis range only went out to 500), and someone else popped off the first slamfire and dumped a bullet into Chesapeake Bay. I think I was the second or third to do so, and dropped my score from winner to first leather. The range officer did not allow a refire for any of us in first relay. By the second relay, the ammo malfunction was quite evident, and refires were given, but nothing was done for those of us in first relay. Slamfires popped all afternoon, was not a pretty sight. On examination, and believe me everyone was looking at ammo that day, the decision was a batch of overly sensitive primers. I guarantee, a slamfire can run your entire day!!!”

Slamfires also happen in mechanisms other than the Garand/M14.

Under Fulton Armory FAR-15 FAQ articles. There is the article “Slamfire: the M16 story” http://www.fulton-armory.com/


This article provides the technical basis and totally refutes those who claim "only high primers" cause slamfires.

This is a recent article, and I thought it provided interesting information on slamfires.

20 Feb 2008 Shotgun News,
Article “ Micro Galil, The Ultimate Krinkov”
Author Peter Kokalis
Page 12

“Most Kalashnikovs have inertia firing pins, without an associated spring. The initial lot of Galils brought into this country by Magnum Research INC. also had no firing pin springs. The Micro Galils that I examined in El Salvador were not equipped with spring-loaded firing pins either.

Military small arms ammunition primers usually have relatively hard cups, which are not easily touched off. American commercial cal .223 Rem ammunition, including Winchester ammunition often features fairly soft primer cups. In 1983, Winchester ammunition in particular caused several slam-fires and all Galils offered for sale in the United States were quickly retrofitted with strong firing pin strings. “