M1A M-14 slam fire
- Thread starter mini14gb
- Start date
- Status
highorder
Member
It's more likely with soft commercial primers, especially if they aren't seated adequately.
I know, that's why I mention commercial grade ammo in my original post. I really hate the slam fire issue of the M1A rifle. I have 2 of them but find myself think about slam fire possibility while readying the rifle to shoot when not using 7.62 military ammo.
Hangingrock
Member
One time with Federal Match ammunition neither Springfield nor Federal accepted responsibility. The rifle a M1A-Supermatch was examined by Springfield and found by them to be with in specification. I sent Federal the unused portion of the ammunition. They responded per their examination that there were no issues with the ammunition.
Over four plus decades of usage I’ve seen slight firing pin indentations on primers with M1 & M1A rifles. That’s why muzzle direction and safety are so very important.
A competitor on the firing line next to me was single loading his AR15 muzzle down on his shooting stool during off hand. He let the bolt go home and the rifle discharged. It didn’t do the contents of his shooting stool any good at all.
Over four plus decades of usage I’ve seen slight firing pin indentations on primers with M1 & M1A rifles. That’s why muzzle direction and safety are so very important.
A competitor on the firing line next to me was single loading his AR15 muzzle down on his shooting stool during off hand. He let the bolt go home and the rifle discharged. It didn’t do the contents of his shooting stool any good at all.
madcratebuilder
Member
Soft skinned primers. One reason I use mil-surp ammo only.
Slamfires with any ammunition are extremely rare events.
I have been accumulating internet reported slamfire incidents in Garands, M1a's, and AR's.
Garands show a much higher incident rate of slamfires than M1a's. In my opinion this is due to the longer, and thus heavier, firing pin found in the Garand. (I just looked, and I only have a reported slamfire with NM military ammo in the M14. The rest are handloads. I want to thank Hangingrock for adding his rare experience.)
The majority of incidents are with handloads. But slamfires in both mechanisms have occurred with military ammo. The attribution is always to "high primers" as the shooting community until recently, believed that only high primers caused slamfires. Now it is being understood that high primers is a subset of causes, not the only cause.
When the M1a/M14 ruled the line, military teams shot Federal Gold medal match out to 300 yards. The Army team dropped the M14 in the early 90’s, and the Marine Team last used the M14 as an across the course rifle in 1996. That was 13 years ago. If there were going to be a number of reports of slamfires with commercial ammunition, it will be from this time period. Unfortunately, hardly anyone who belonged to the AMU or USMC teams from that period is on these boards, and hardly anyone who shot prior to that is on these boards.
Back then, while people “heard of slamfires” in Garands and M1a’s, they were adamant that AR’s could not slamfire. Now that AR’s are the 99% service rifle on the firing line, there are enough of them that the rare slamfire fire event is happening in them, and being reported.
I have been accumulating internet reported slamfire incidents in Garands, M1a's, and AR's.
Garands show a much higher incident rate of slamfires than M1a's. In my opinion this is due to the longer, and thus heavier, firing pin found in the Garand. (I just looked, and I only have a reported slamfire with NM military ammo in the M14. The rest are handloads. I want to thank Hangingrock for adding his rare experience.)
The majority of incidents are with handloads. But slamfires in both mechanisms have occurred with military ammo. The attribution is always to "high primers" as the shooting community until recently, believed that only high primers caused slamfires. Now it is being understood that high primers is a subset of causes, not the only cause.
When the M1a/M14 ruled the line, military teams shot Federal Gold medal match out to 300 yards. The Army team dropped the M14 in the early 90’s, and the Marine Team last used the M14 as an across the course rifle in 1996. That was 13 years ago. If there were going to be a number of reports of slamfires with commercial ammunition, it will be from this time period. Unfortunately, hardly anyone who belonged to the AMU or USMC teams from that period is on these boards, and hardly anyone who shot prior to that is on these boards.
Back then, while people “heard of slamfires” in Garands and M1a’s, they were adamant that AR’s could not slamfire. Now that AR’s are the 99% service rifle on the firing line, there are enough of them that the rare slamfire fire event is happening in them, and being reported.
Ed Harris
Member
I have examined several M1 Garand, Ruger Mini-14 and M1A rifles which have slam-fired.
All such incidents I am personally aware of occurred using handloads.
1) While soft primers may be a contributing factor, this is not the sole explanation.
2) If primers are not seated below flush of the case head, protrusion of the primer cup above the case head is a factor.
3) If cases are not sized and trimmed properly, so that there is resistance to full bolt closure and lockup, this is another factor. Both sized cases and loaded rounds should be gaged 100%. Use of military ammunition in minimum SAAMI or custom "match" chambers can also cause tolerance stacking interference.
4) When the rifle is properly assembled, with correct parts which gage properly, the firing pin should be flush or below the bolt face at "half-lock" (7-1/2 degrees bolt rotation on the M14). This is measured using a stripped bolt and slave slide-handle using a dial indicator gage inserted from the muzzle.
5) When M1a parts guns are assembled with surplus parts which may have been rejected because they didn't gage up, this is a big factor.
6) If the firing pin retraction cam in the receiver web doesn't gage properly this is another factor.
7) If the "tail" of the firing pin which engages the receiver retraction cam does not gage properly, this is a factor.
8) If primer pockets are loose from repeated reloads of brass having head hardness less than 170Vickers Diamond Pyramid Hardness, loose primers, or blown primers which leave debris in the bolt face can also cause a slam-fire.
Slam-fires have not to my knowledge been documented in properly assembled rifles in which all parts in the assembly meet the government gages, when using either NATO, US military or SAAMI specification commercial match ammunition, such as M80, L2A2, M118, M852 or Federal #308M.
An exact attributing cause of any slamfire is often impossible to determine because of interaction of multiple variables and the fact that "the Brass Fairy" often removes much of the evidence.
All such incidents I am personally aware of occurred using handloads.
1) While soft primers may be a contributing factor, this is not the sole explanation.
2) If primers are not seated below flush of the case head, protrusion of the primer cup above the case head is a factor.
3) If cases are not sized and trimmed properly, so that there is resistance to full bolt closure and lockup, this is another factor. Both sized cases and loaded rounds should be gaged 100%. Use of military ammunition in minimum SAAMI or custom "match" chambers can also cause tolerance stacking interference.
4) When the rifle is properly assembled, with correct parts which gage properly, the firing pin should be flush or below the bolt face at "half-lock" (7-1/2 degrees bolt rotation on the M14). This is measured using a stripped bolt and slave slide-handle using a dial indicator gage inserted from the muzzle.
5) When M1a parts guns are assembled with surplus parts which may have been rejected because they didn't gage up, this is a big factor.
6) If the firing pin retraction cam in the receiver web doesn't gage properly this is another factor.
7) If the "tail" of the firing pin which engages the receiver retraction cam does not gage properly, this is a factor.
8) If primer pockets are loose from repeated reloads of brass having head hardness less than 170Vickers Diamond Pyramid Hardness, loose primers, or blown primers which leave debris in the bolt face can also cause a slam-fire.
Slam-fires have not to my knowledge been documented in properly assembled rifles in which all parts in the assembly meet the government gages, when using either NATO, US military or SAAMI specification commercial match ammunition, such as M80, L2A2, M118, M852 or Federal #308M.
An exact attributing cause of any slamfire is often impossible to determine because of interaction of multiple variables and the fact that "the Brass Fairy" often removes much of the evidence.
Last edited:
Art Eatman
Moderator In Memoriam
I bought a new M1A in 1984; target version. Went out to my benchrest with GI ammo. First two rounds were an immediate double. No damage to anything, so I guessed it was close enough to in-battery to be okay.
So, I removed the trigger group. No obvious flaw. I phoned Springfield and basically said, "Houston, we have a problem."
Fastest mail service I ever got, for a new trigger group. No problems thereafter.
SFAIK, the disconnect didn't disconnect. I later read that other people had had a similar problem. Engagement of the disconnect was said to be the culprit.
So, I removed the trigger group. No obvious flaw. I phoned Springfield and basically said, "Houston, we have a problem."
Fastest mail service I ever got, for a new trigger group. No problems thereafter.
SFAIK, the disconnect didn't disconnect. I later read that other people had had a similar problem. Engagement of the disconnect was said to be the culprit.
Hangingrock
Member
The receiver and bolt were replaced.
Hey mini14gb, have a gunsmith check your trigger pull weight...s/b about 4 1/2lbs.
If the slamfire is the same as doubling, you can add 2 more...the last two I owned.
Both new, out-of-the-box Springfield M1As. Both would double with ANY ammo. That is, shoot 2 times with one pull of the trigger. Startling to say the least. Folks eyeballed me good on the firing line.
Called SA and was told to either shoot standing up or load singly if firing from a bench. No joke. Yeah, thats what I paid big bucks for...a freaking M1A single-shot! Even after I told him the triggers on both were too light (2 3/4lb instead of 4 1/2lb). He wasn't even interested....
Sold one, had a smith (a match shooter himself) fix the other. Worked okay after that but I never felt confident with the weapon...or any future dealings with the Reese Bros.
YMMV
Good Luck
If the slamfire is the same as doubling, you can add 2 more...the last two I owned.
Both new, out-of-the-box Springfield M1As. Both would double with ANY ammo. That is, shoot 2 times with one pull of the trigger. Startling to say the least. Folks eyeballed me good on the firing line.
Called SA and was told to either shoot standing up or load singly if firing from a bench. No joke. Yeah, thats what I paid big bucks for...a freaking M1A single-shot! Even after I told him the triggers on both were too light (2 3/4lb instead of 4 1/2lb). He wasn't even interested....
Sold one, had a smith (a match shooter himself) fix the other. Worked okay after that but I never felt confident with the weapon...or any future dealings with the Reese Bros.
YMMV
Good Luck
Last edited:
VA27
Member
We've had 120 M14's in service for over 10 years, shooting nothing but commercial ammo. NO slamfires to date.
nbkky71
Member
The few times I've heard about a slamfire with an M1A/M14, the issue was with the shooter dropping a round directly into the chamber and releasing the bolt.
When single loading the M1A/M14 snap a round into the top of the magazine and then release the bolt. That's the way I was taught when I shot the M1A competitively.
When single loading the M1A/M14 snap a round into the top of the magazine and then release the bolt. That's the way I was taught when I shot the M1A competitively.
What an interesting statement to put IN BOLD. Like Moses coming off the mountain with the tablets. God must have said it. But this information came from the wrong burning bush.
You have so many caveats, A: “properly assembled rifles”, b: “meet government gages”, C: “using NATO, US Military or SAAMI specification commercial match ammunition”.
Well of course slamfires occurred with LC Match, US Military ammunition. But the occurrence was very low and when was White Box last made, 79? . Is M852 even being made anymore?
And who is shooting this stuff?: basically no one, and certaintly not in enough quantities to produce a flood of reported slamfires.
But there are a few. You could not convince a denier like HugoEstupido that any meets the A:B:C of your statement, but in the first report they were shooting LC match. I assume since it was an All Army match the M14 was Government. Built by an experienced match armorer.
This guy had a DCM Garand grenade with LC69.
This shooter was using a military match rifle with military issued match ammo, (was the military using commercial match ammo back in 1968?) and there were lots of in battery slamfires.
308 Garand Slamfires with Military Match Ammunition.
CMP Garands with Greek Ball
The basic assumption you make in your statement is something whith which I disagree: that the receiver bridge is an effective measure against slamfires.
It is not. It never was. The Garand always had slamfires. That is why the round Garand firing pin is such collector’s item. There is a dimple on each and every primer of every round ever chambered in a M1a or Garand. This ought to be a clue that the free floating firing pin contained within the bolt is hitting primers with force.
Given an overly sensitive primer, the only issue in question is, will the shooter have an inbattery slamfire, or an out of battery slamfire?
The basic Garand mechanism does not retract the firing pin until final cam down. That is about .006” of movement at most. And yet in battery slamfires happen. This is evidence that the receiver bridge is not working.
So the theories on which the dogma that slamfires don't happen in properly assembled rifles in which all parts in the assembly meet the government gages, when using either NATO, US military” is based is on incorrect assumptions and incomplete knowledge.
Last edited:
- Status
Similar threads
