Was it a slamfire?

JM at Work · November 7, 2002, 03:52 PM

Took some reloads to the range near sunset yesterday... 30-06 loads in my "new" M1.

I only got to fire two clips before it got dark, and on the second one I was counting shots and on the 4th or 5th one I thought that the rifle "double tapped" on me... very, very quick, wasn't sure what I saw (thought I saw a double muzzle-flash) and only counted to 7 before the clip ejected.

I was reading about the slamfire-in-M1 thread recently, and wondered if my Winchester primers are the likely cause of what happened.

If so, I'll scrape up the money to get CCI before I reload anything else, and use the WLR for my .30-30.

If not, I'll suspect my new babe needs to be checked by the doc.

-Jorah

saands · November 7, 2002, 07:34 PM

I had that happen to me with milsurp ammo so I knew it wasn't the primers ... my secondary sear wasn't reliably engaging and I fixed it with a replacement trigger module (fortunately, I had just bought it from AIM). It's funny how a double-tap is hard to detect ... now if it were a 100% problem and it went full-auto, you'd know for sure

and this needs to be taken care of ASAP as the condition is dangerous. As a potential test for the slamfire, I'd let the bolt fly home and then eject the cartridge without firing it and look at the dimple ... I think that there will be something on all of them, but it shouldn't be too deep.

Saands

cheygriz · November 7, 2002, 10:38 PM

JM,

Primers can cause slamfires in the M-1. Remington 9 1/2 standard large rifle primers meet Milspec. They are the same primers Remington loads in their military ammo.

I've heard that CCI makes a special order primer that meets Milspec, but I'ver never seen one.

If you're eliminated other possibilities, change primers. In facxt, it might be a good idea to change primers anyway.

I will use nothing but Remington Milspec primers, 9 1/2 large rifle, and 7 1/2 small rifle in any ammo that I load for military rifles.

Steve Smith · November 7, 2002, 10:55 PM

It could have slamfired, but it is also easy for an M1 to bump fire if you milk the trigger. Be sure to make a positive movement with your trigger finger when firing it.

JM at Work · November 8, 2002, 07:03 AM

cheygriz, thanks for the info on primers... I'll look for those.

Steve, I'll try to figure out what I'm doing with the trigger. I'm usually just trying for a smooth surprise break, and haven't thought about other issues.

saands, I'll watch that sear issue. If, after changing to harder primers and analyzing my trigger work, I still get double taps, I'll see if I can find an M1 trigger doctor to look at it.

Thanks, guys!

Sunday is my first match since getting my rifle from CMP... I have high hopes of finally getting out of last place in the standings.

-Jorah

swampyMO · November 8, 2002, 07:46 AM

JM at work,

Steve Smith has the right of it in this case.

Shooting an M1 or M14 from a bench with the butt loose in your shoulder can lead to "bump firing" or doubling. Mechanically the rifle is functioning perfectly normal, it is only reacting to recoil and firing again as it bounces off of your shoulder and back into your trigger finger.

This will stop if you just have the butt firmly into your shoulder when you fire from a bench. It also helps to have a firm follow through on your trigger squeeze.

If you do get it firm into your shoulder and it still happens frequently, then I'd have a good M1 smith check your trigger group for worn sear and hammer...

Re Slam Fire: This is definitely a concern with the M1-M14. Making sure you have fully seated your primers is mandatory for safe handloads with these rifles. Also part of this equation is full length resizing of the brass and keeping the chamber clean.

I seriously doubt that what you experienced was a true slam fire. A true out of battery slam fire would REALLY get your attention as this usually happens before the bolt is fully locked up. If an out of battery slam fire does occur pieces and parts of the rifle can and do "go ballistic".... The firearms equivalent of an Indy car after a header into the wall. Not pretty and seldom happens to the same rifle twice.

Garands forever,
Swampy

JM at Work · November 8, 2002, 12:09 PM

is that I wasn't sure what a slamfire was... I'm still confused.

But... I actually was firing off-hand, and since I'm still very new to large rifles, I was paying a lot of attention to how I had it tucked into my shoulder...

I can assure everyone that I'll be watching myself and the gun carefully for the foreseeable future, trying to figure out exactly what is going on.

I do full-length resize, and I clean the rifle after every trip to the range, so I can rule that out.

Thanks for the advice, guys!

-Jorah

Steve Smith · November 8, 2002, 12:36 PM

The M1, M14, AR15s have floating firing pins, meaning they don't have a spring to hold them back when the bolt closes. Because of this, if you have a filthy chamber and the cartridge stops short, or a too-tight headspace (same thing as filthy chamber), or a high primer, or a bolt going too fast, the firing pin can hit the primer and ignite the cartridge. If you charge the rifle, and then extract the loaded round, you'll see that the firing pin has already hit the primer. Completely normal.

Again, I think you doubled the rifle with a milked trigger pull (you didn't follow through with your finger), and under recoil the sear reset and then in the "negative" or "reverse" recoil the sear tripped again because your finger had not moved, firing the rifle. I don't know of many that have not done this when learning the ropes.

BTW, it is imperative that you single load an M1 or M14 from the magazine (the M1 has a fixed internal magazine) rather than plopping the cartridge in the chamber or in top of the follower and closing the bolt. With the M1, insert the en bloc clip, then put a round or two under the clip lips and on the follower. This will slow the bolt slightly and reduce the chance of slamfire, which happens most often when single loading.

saands · November 8, 2002, 12:37 PM

I imagine that someone will correct me if I am mistaken, but my understanding of a slamfire is that it is the firing of a round due to the firing pin striking the primer without the pull of the trigger (in a gun not designed to operate in this fashion ... think Sten). This can happen for at least two general reasons:
1. Many semi-auto weapons have free floating firing pins. this leads to the firing pin continuing to travel forward after the bolt closes ... normally the pin isn't travelleing nearly fast enough to actually fire the next round, but quite often it is travelling fast enough to leave a tiny ding on the primer. If you have the wrong firing pin (too heavy) or your weapon has a spring in front of the pin that is missing or if your primers are too soft (using small pistol primers 'cuz you ran out of small rifle primers?) then this can lead to the automatic detonation of subsequent rounds.
2. Your firing pin is stuck out! This can happen easily with rifles that have been stored in cosmoline for years and never received a thorough cleaning ... the SKS's seem to be good candidates for this failure as some people believe that they actually never require cleaning

Mine never did that, but mine are so clean that you could mince garlic with my bolts and not taste the difference in your fettucini. I think that a legal select fire rifle would be tons of fun, but the thought of one of my semi's going auto on me is too scary ... especially since it could start when letting the bolt fly forward to chamber the first round ... no trigger pull at all! I won't take chances there.

It is good to understand how your weapons function ... you might be surprised! As an engineer, the whole free-floating firing pin seems a little too close to the edge for me, but over the years the results seem to state that the design has some margin ... but you should know that it isn't bullet-proof. For that reason, I won't chamber a round in the SKS inside the house unless I am preparing to fire that round inside the house. My 1911, on the other hand, doesn't ding the primer at all, so that's a different deal.

I think I got it mostly right ... hope it helps
Saands

Steve Smith · November 8, 2002, 12:43 PM

"Your firing pin is stuck out! "

Another possibility. Firing pin channel should be DRY and clean.

JM at Work · November 8, 2002, 02:41 PM

I've had the rifle in pieces, soaked the whole trigger assembly in Ed's Red and then cleaned it off with Hoppe's but the firing pin channel probably isn't dry.

I'll strip the thing and take a look... I don't even know where the pin is at the moment (I was concentrating on getting the rifle back together, not paying attention to the trigger assembly the first time)

Good stuff, folks. I can feel my brain "boiling..." a sure sign I'm learning a lot.

-Jorah

PS:

Quote:

my understanding of a slamfire is that it is the firing of a round due to the firing pin striking the primer without the pull of the trigger

Good, that's what I thought it was... I just didn't know that there were so many possible causes.

.

John Lawson · November 8, 2002, 07:47 PM

Most "slamfires" I've investigated weren't slamfires at all. If you hold the pistol grip too loosely and squeeze off like you are shooting a .22, the rifle stock can recoil into your shoulder and rebound against your trigger finger, firing another shot.
Grip the rifle hard and keep constant pressure against the trigger; then see if you get a double.

Jorah Lavin · November 10, 2002, 10:28 AM

I fired 72 rounds yesterday, carefully watching my grip on the stock, and how I was holding the rifle back against my shoulder (all shots fired off a sandbag front rest) and trying to pay attention to my trigger work.

I got some good (for me) groups (particularly after I realized that my rear sight was loose and creaping down on me!) and no mis-fires, double-taps, or anything else wrong.

Thanks for the educational thread, folks.

-Jorah

buford1 · November 12, 2002, 04:09 AM

I have only seen one slam fire and you damn sure know It happend. Now I may be wrong but dosnt a slam fire occur before the bolt locks up. thats something you will remember.and not forget. Dug crap from my friends hands and face for hours. Good thing he was wearing glasses.

foghornl · November 19, 2002, 11:14 AM

Visit

www.fultonarmory.com

and look in the M-1 "FAQ" section. There is some good info on slamfires, high primers, single-loads, etc.

alan · November 23, 2002, 01:16 AM

JM at work:

What is a slam fire? DANGEROUS.

With the M-1 Rifle, most likely caused by high primers, improperly seated primers. Could be due to other causes mentioned previously, but I suspect high primers would be the most likely cause.

Supposedly, as I recall, there was a design feature in the M-1 that "prevented" the rifle from firing unlocked, but then there is Murphy's Law. Watch primer seating.

November 7, 2002, 03:52 PM	#1
JM at Work Junior member Join Date: August 23, 2002 Location: Central NC Posts: 35	Was it a slamfire? Took some reloads to the range near sunset yesterday... 30-06 loads in my "new" M1. I only got to fire two clips before it got dark, and on the second one I was counting shots and on the 4th or 5th one I thought that the rifle "double tapped" on me... very, very quick, wasn't sure what I saw (thought I saw a double muzzle-flash) and only counted to 7 before the clip ejected. I was reading about the slamfire-in-M1 thread recently, and wondered if my Winchester primers are the likely cause of what happened. If so, I'll scrape up the money to get CCI before I reload anything else, and use the WLR for my .30-30. If not, I'll suspect my new babe needs to be checked by the doc. -Jorah

November 7, 2002, 10:38 PM	#3
cheygriz Senior Member Join Date: May 11, 2002 Location: high up in the rockies Posts: 2,289	JM, Primers can cause slamfires in the M-1. Remington 9 1/2 standard large rifle primers meet Milspec. They are the same primers Remington loads in their military ammo. I've heard that CCI makes a special order primer that meets Milspec, but I'ver never seen one. If you're eliminated other possibilities, change primers. In facxt, it might be a good idea to change primers anyway. I will use nothing but Remington Milspec primers, 9 1/2 large rifle, and 7 1/2 small rifle in any ammo that I load for military rifles. __________________ If you think a mighty military force is expensive, wait 'til you see what a weak one costs.

November 7, 2002, 10:55 PM	#4
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	It could have slamfired, but it is also easy for an M1 to bump fire if you milk the trigger. Be sure to make a positive movement with your trigger finger when firing it. __________________ Favor the X. Steve Smith NRA Life Member

November 8, 2002, 07:03 AM	#5
JM at Work Junior member Join Date: August 23, 2002 Location: Central NC Posts: 35	I'll work to control what I can... watch for signs of sear trouble cheygriz, thanks for the info on primers... I'll look for those. Steve, I'll try to figure out what I'm doing with the trigger. I'm usually just trying for a smooth surprise break, and haven't thought about other issues. saands, I'll watch that sear issue. If, after changing to harder primers and analyzing my trigger work, I still get double taps, I'll see if I can find an M1 trigger doctor to look at it. Thanks, guys! Sunday is my first match since getting my rifle from CMP... I have high hopes of finally getting out of last place in the standings. -Jorah

November 8, 2002, 12:09 PM	#7
JM at Work Junior member Join Date: August 23, 2002 Location: Central NC Posts: 35	One of the reasons I asked is that I wasn't sure what a slamfire was... I'm still confused. But... I actually was firing off-hand, and since I'm still very new to large rifles, I was paying a lot of attention to how I had it tucked into my shoulder... I can assure everyone that I'll be watching myself and the gun carefully for the foreseeable future, trying to figure out exactly what is going on. I do full-length resize, and I clean the rifle after every trip to the range, so I can rule that out. Thanks for the advice, guys! -Jorah

November 7, 2002, 07:34 PM	#2
saands Senior Member Join Date: November 14, 1999 Posts: 1,573	I had that happen to me with milsurp ammo so I knew it wasn't the primers ... my secondary sear wasn't reliably engaging and I fixed it with a replacement trigger module (fortunately, I had just bought it from AIM). It's funny how a double-tap is hard to detect ... now if it were a 100% problem and it went full-auto, you'd know for sure and this needs to be taken care of ASAP as the condition is dangerous. As a potential test for the slamfire, I'd let the bolt fly home and then eject the cartridge without firing it and look at the dimple ... I think that there will be something on all of them, but it shouldn't be too deep. Saands

November 8, 2002, 07:46 AM	#6
swampyMO Senior Member Join Date: December 29, 1999 Location: Missouri Posts: 327	JM at work, Steve Smith has the right of it in this case. Shooting an M1 or M14 from a bench with the butt loose in your shoulder can lead to "bump firing" or doubling. Mechanically the rifle is functioning perfectly normal, it is only reacting to recoil and firing again as it bounces off of your shoulder and back into your trigger finger. This will stop if you just have the butt firmly into your shoulder when you fire from a bench. It also helps to have a firm follow through on your trigger squeeze. If you do get it firm into your shoulder and it still happens frequently, then I'd have a good M1 smith check your trigger group for worn sear and hammer... Re Slam Fire: This is definitely a concern with the M1-M14. Making sure you have fully seated your primers is mandatory for safe handloads with these rifles. Also part of this equation is full length resizing of the brass and keeping the chamber clean. I seriously doubt that what you experienced was a true slam fire. A true out of battery slam fire would REALLY get your attention as this usually happens before the bolt is fully locked up. If an out of battery slam fire does occur pieces and parts of the rifle can and do "go ballistic".... The firearms equivalent of an Indy car after a header into the wall. Not pretty and seldom happens to the same rifle twice. Garands forever, Swampy

November 8, 2002, 12:36 PM	#8
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	The M1, M14, AR15s have floating firing pins, meaning they don't have a spring to hold them back when the bolt closes. Because of this, if you have a filthy chamber and the cartridge stops short, or a too-tight headspace (same thing as filthy chamber), or a high primer, or a bolt going too fast, the firing pin can hit the primer and ignite the cartridge. If you charge the rifle, and then extract the loaded round, you'll see that the firing pin has already hit the primer. Completely normal. Again, I think you doubled the rifle with a milked trigger pull (you didn't follow through with your finger), and under recoil the sear reset and then in the "negative" or "reverse" recoil the sear tripped again because your finger had not moved, firing the rifle. I don't know of many that have not done this when learning the ropes. BTW, it is imperative that you single load an M1 or M14 from the magazine (the M1 has a fixed internal magazine) rather than plopping the cartridge in the chamber or in top of the follower and closing the bolt. With the M1, insert the en bloc clip, then put a round or two under the clip lips and on the follower. This will slow the bolt slightly and reduce the chance of slamfire, which happens most often when single loading. __________________ Favor the X. Steve Smith NRA Life Member

November 8, 2002, 12:37 PM	#9
saands Senior Member Join Date: November 14, 1999 Posts: 1,573	I imagine that someone will correct me if I am mistaken, but my understanding of a slamfire is that it is the firing of a round due to the firing pin striking the primer without the pull of the trigger (in a gun not designed to operate in this fashion ... think Sten). This can happen for at least two general reasons: 1. Many semi-auto weapons have free floating firing pins. this leads to the firing pin continuing to travel forward after the bolt closes ... normally the pin isn't travelleing nearly fast enough to actually fire the next round, but quite often it is travelling fast enough to leave a tiny ding on the primer. If you have the wrong firing pin (too heavy) or your weapon has a spring in front of the pin that is missing or if your primers are too soft (using small pistol primers 'cuz you ran out of small rifle primers?) then this can lead to the automatic detonation of subsequent rounds. 2. Your firing pin is stuck out! This can happen easily with rifles that have been stored in cosmoline for years and never received a thorough cleaning ... the SKS's seem to be good candidates for this failure as some people believe that they actually never require cleaning Mine never did that, but mine are so clean that you could mince garlic with my bolts and not taste the difference in your fettucini. I think that a legal select fire rifle would be tons of fun, but the thought of one of my semi's going auto on me is too scary ... especially since it could start when letting the bolt fly forward to chamber the first round ... no trigger pull at all! I won't take chances there. It is good to understand how your weapons function ... you might be surprised! As an engineer, the whole free-floating firing pin seems a little too close to the edge for me, but over the years the results seem to state that the design has some margin ... but you should know that it isn't bullet-proof. For that reason, I won't chamber a round in the SKS inside the house unless I am preparing to fire that round inside the house. My 1911, on the other hand, doesn't ding the primer at all, so that's a different deal. I think I got it mostly right ... hope it helps Saands

November 8, 2002, 12:43 PM	#10
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	"Your firing pin is stuck out! " Another possibility. Firing pin channel should be DRY and clean. __________________ Favor the X. Steve Smith NRA Life Member

November 8, 2002, 07:47 PM	#12
John Lawson Senior Member Join Date: August 28, 1999 Posts: 281	Most "slamfires" I've investigated weren't slamfires at all. If you hold the pistol grip too loosely and squeeze off like you are shooting a .22, the rifle stock can recoil into your shoulder and rebound against your trigger finger, firing another shot. Grip the rifle hard and keep constant pressure against the trigger; then see if you get a double. __________________ "Politicians are bilgewater in the ship of state."

November 10, 2002, 10:28 AM	#13
Jorah Lavin Senior Member Join Date: April 4, 1999 Location: Indian Land, SC USA Posts: 593	Post-range trip followup I fired 72 rounds yesterday, carefully watching my grip on the stock, and how I was holding the rifle back against my shoulder (all shots fired off a sandbag front rest) and trying to pay attention to my trigger work. I got some good (for me) groups (particularly after I realized that my rear sight was loose and creaping down on me!) and no mis-fires, double-taps, or anything else wrong. Thanks for the educational thread, folks. -Jorah

November 12, 2002, 04:09 AM	#14
buford1 Senior Member Join Date: May 6, 2002 Location: long beach.CA Posts: 116	I have only seen one slam fire and you damn sure know It happend. Now I may be wrong but dosnt a slam fire occur before the bolt locks up. thats something you will remember.and not forget. Dug crap from my friends hands and face for hours. Good thing he was wearing glasses.

November 19, 2002, 11:14 AM	#15
foghornl Senior Member Join Date: March 18, 2002 Location: Ohio Posts: 1,354	Visit www.fultonarmory.com and look in the M-1 "FAQ" section. There is some good info on slamfires, high primers, single-loads, etc. __________________ Load your weapons and 'Stand Ready'. It will be a bumpy ride.

November 23, 2002, 01:16 AM	#16
alan Senior Member Join Date: June 7, 1999 Posts: 3,847	JM at work: What is a slam fire? DANGEROUS. With the M-1 Rifle, most likely caused by high primers, improperly seated primers. Could be due to other causes mentioned previously, but I suspect high primers would be the most likely cause. Supposedly, as I recall, there was a design feature in the M-1 that "prevented" the rifle from firing unlocked, but then there is Murphy's Law. Watch primer seating.