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Old March 13, 2011, 02:37 PM   #1
Webleymkv
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My FN-49 Blew Up!

Well, sort of. I was at the range Friday and I experienced what I think was an out-of-battery ignition. I was shooting my AL FN-49 with Winchester 150grn Power Point JSP (factory ammo, not reloads) and on the third or fourth shot (I wasn't really counting) I noticed that it was much louder and that I felt some powder residue hit me in the face. I immediately locked the bolt open and removed the magazine in order to get the rest of the unfired cartridges out. It was then that I noticed that the bolt would not go foreward because of a shard of brass blocking it, the stock was cracked in front of the magazine, and the reciever cover retainer and sliding dust cover were bent outward. I managed to remove the shard of brass and get the bolt closed, but needless to say I was done shooting that particular gun for tha day.

I later managed to find most of the culprit shell casing which was mangled beyond belief. When I got home, I took the rifle apart and repaired the crack in the stock and bent the reciever cover retainer back into shape (the dust cover fell off when I was inspecting it, but it was already bent and really needed to be replaced anyway). I also disassembled the bolt (I'd already replaced the one-piece firing pin with the later two-piece design) and inspected the trigger, sear, hammer, and auxillary sear and I couldn't find any obvious reason for the accident.

Yesterday, I took the rifle and the magnled casing to the gunsmith at my local Gander Mountain. He seemed to be fairly familiar with FN-49's as his first question was about whether or not I had the one-piece or two-piece firing pin. He inspected the rifle and told me that it was mechanically fine and that the only two reasons he could think of for the mishap were either debris stuck in the firing pin channel or a defective round of ammunition.

I very highly doubt that debris in the firing pin channel was the cause because the rifle had only fired two or three shots before the incident and was cleaned prior to that (I always clean my guns every time I fire them) and the only lube I'd ever used on this particular gun has been a very light coating of oil (usually Remoil). Also, the firing pin was not protruding immediately after the incident, when I disassembled the rifle at home, or when the gunsmith inspected it. This leads me to believe that the ammo was probably the culprit and I plan to send an e-mail to Winchester about the incident.

Honestly, I think it's probably a testament to the design of the rifle that I was not injured and that the gun wasn't damaged any worse than it was. Even so, I'm probably going to sell this rifle now (though at least I can do it with a clear conscience given the gunsmith OK) as it scared me pretty badly. As I was researching the problem Friday night, I read on a couple of forums that FN-49's are somewhat known for slamfires and OOB ignitions and that they can be kind of sensitive about commercial ammo's softer primers. Since I don't reload 30-06 and milsurp ammo is getting scarce, I really have little use for a rifle in that caliber that I can't shoot commercial ammo in. Also, I find myself somewhat questioning the need for a semi-auto in a full-caliber cartridge (particularly when my K-31 is so slick).
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Old March 13, 2011, 04:17 PM   #2
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First and foremost, I'm glad you nor any bystander was hurt.

Second, you mind posting some pics? I'd like to see what the hubbub was all about...
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Old March 13, 2011, 04:45 PM   #3
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I'll see if I can't borrow a digital camera to snap some decent pics with. Honestly, other than a missing dust cover it's difficult to tell that anything happened to the rifle as the cracked stock was the worst damage and I've already repaired it. The spent casing, on the other hand, is another story. The case head is nearly separated and the rest of the case looks like someone rung it out like a wet dish towel. I really feel fortunate that I didn't have to pick anything out of my face and I'm suprised that I didn't have to clean out my trousers afterward.
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Old March 13, 2011, 06:36 PM   #4
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Yes, please provide pictures.

I have handled FN 49’s, I assume that it has the same free floating firing pin arrangement that FAL’s have.

Quote:
Yesterday, I took the rifle and the magnled casing to the gunsmith at my local Gander Mountain. He seemed to be fairly familiar with FN-49's as his first question was about whether or not I had the one-piece or two-piece firing pin. He inspected the rifle and told me that it was mechanically fine and that the only two reasons he could think of for the mishap were either debris stuck in the firing pin channel or a defective round of ammunition.
For decades, the NRA and the ex Ordnance Department employees writing for the American Rifleman, kept up a campaign to wish away slamfires in Garands. Being total suck ups to their former employer (the Army) who was providing a lot of resources to their sport and their magazine, they would not acknowledge that primer sensitivity was a real cause of slamfires, instead they wrote articles claiming that only defective Garands , or only defective ammunition (high primers) could slamfire out of battery. They would not, and neither will their acolytes, acknowledge that mechanisms with free floating firing pins will slamfire given a sensitive primer. And they would never have agreed that the Garand design is defective, prone to slamfiring out of battery, instead they were always blame shifting to the owner/operator. For decades the Garand and the M1a were the only semi auto’s on the market, foreign jobs, like yours, were just not around or were not fired enough to reveal the interesting characteristics they have.

From the answer you got from the Gander Mountain man “its all your fault”, it sure sounds like he is one of those old school acolytes.

You will see this sort of thinking in old legacy posts from Bart Bobbitt. The link is in this thread http://thefiringline.com/forums/show...9&postcount=40

And my reply was here http://thefiringline.com/forums/show...4&postcount=41

Even though Bart actually witnessed slamfires, he could not and would not acknowledge that primer sensitivity was the cause. His convoluted explanation of the evidence before him is all based on the group think of the era: that only high primers or defective guns have slamfires.

Until that generation is below the ground, and silent for decades, you will continue to hear the same wrong answer.

Winchester redesigned their primers around 1999 to make them more sensitive. I called and was told “this was to combat off center firing pin hits.”.

I will bet that your firing pin is especially heavy.

I am going to assume that FN49’s and FAL’s have similar free floating firing pins. I am aware of a Gun Club bud who loaded ammunition with brass finish WLR and the gun slamfired, in battery thank goodness, when he put a round in the chamber and dropped the bolt. This is how the military manual told him to load the thing single shot. The slamfire so un nerved him, he left for home and did not fire another round. He told me he disassembled the mechanism, everything was as clean as the night before, and there were no broken parts.

There are reports from the web with slamfires in FAL’s.

It is obvious that given a sensitive primer, FAL’s will slamfire. If you are unlucky, it will slamfire out of battery.

I would recommend never using Winchester ammo again and to roll your own. I recommend the use of “mil spec” primers, which are less sensitive than the commercial brands. CCI#34’s are advertized as mil spec, I have read that some Russian primers are harder than rocks. That is just great. Less sensitive is better than more sensitive in these military rifles. I will recommend small base sizing, use a case gage and size to gage minimum, seat all primers by hand to ensure that all are below the case head.



Quote:

FAL Slamfire

http://www.thehighroad.org/showthrea...05910&posted=1

Today, 04:27 PM
#18

W.E.G.
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Join Date: 09-26-06
Location: all over Virginia
Posts: 1,812 I slam-fired a FAL once.

Lake City M852 ammo.

Entreprise receiver.

1.633 headspace.

Tossed the round in the chamber.

Slingshot the charging handle.

Fired as soon as the bolt slammed.

Lucky it was in-battery.

I'd like to know what kind of ammo was involved in the KB mentioned in the OP.
I don't know what is "white box surplus."






http://www.falfiles.com/forums/showt...e+or+slam+fire

This was in a discussion of slamfires and FALs, I this guy had a slamfire in a FAL with US LC M852 match ammo.

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FALaholic # 1211 June 26, 2008 07:57






FAL Files:

Slamming the bolt may cause a slam-fire.

I didn't believe it until it finally happened to me.

I was firing 600 yards from a prone position.
I tossed one shiny new round of Lake City M852 into the chamber, and thumbed the BHO.
The rifle fired at the moment the bolt slammed home.
My 600 yard groups were already sucking beyond belief (all over the 6 and 7 ring).
Expensive TASCO "World Class" scope went T/U that day.

The slam-fire was just the icing on the cake for a day when pretty much everything was going wrong.


FAL doubling leading to ATF seizure.
http://www.falfiles.com/forums/showt...hreadid=183318
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 never tried to shoot the fal with the selector on FA for the obvious reason of knowing that it could only fire out of battery that to do so would be risking a dangerous outcome.
I also would never shoot expensive hunting ammo $15 a box of 20.

The HTS set (DSA) was not doubling

I work with a Class 2 manf. and I have no reason to shoot a illegal MG we have all the legal ones we could ever need.

The ATF agent that confiscated my FAL's did not do the test he took the rifles to the tech branch in DC where they were "tested"

After many months and $ my lawyer, expert witness and I got to do our test with the ATF and we video taped it and that is when the truth was shown.

A local gun dealer here in NC By the name of Dan D. who for some reason did not like me actually turned the ATF my way by telling them a bunch of lies.

After the many man hours spent on my behalf I think the atf just tried to salvage a conviction of an innocent person to justify all the time spent in their investigation of me.

It is a long story but this sheds light on the jist of it.

I just this week was given back my property except for the one rifle that malfunctoned.

Thanks to diligent work by my Lawyer
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Last edited by Slamfire; March 13, 2011 at 06:57 PM.
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Old March 13, 2011, 08:36 PM   #5
Webleymkv
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I have handled FN 49’s, I assume that it has the same free floating firing pin arrangement that FAL’s have.
Actually, the FN-49 does not have a free-floating firing pin. The original design for the bolt was a one-piece firing pin, a firing pin return spring, and a couple different types of firing pin block that would prevent the firing pin from traveling forward unless the bolt was in battery (though some of the Egyptian-contract 8mm guns lack the FP block). Later, it was found that the one-piece firing pin was prone to breakage and would cause the forward section to stick and the gun to go full-auto. Because of this, the firing pin design was changed to a two-piece design although the FP block only acts on the rear section. The front section of the firing pin is quite light and is held rearward until the trigger is pulled by the firing pin return spring.

I've had issues with this rifle slam-firing before but thought I had fixed them. Before, the gun would intermittently fire 2-3 rounds with a single pull of the trigger, but never out-of-battery. I replaced the older one-piece firing pin with a newer two-piece one and replaced the firing pin return spring with an extra-heavy one. This seemed to fix the issue when I used Federal Power-Shok ammo (the type I normally use in this rifle because I usually find it the cheapest). The incident in question was the first time that I'd used Winchester ammo in several years (I did run a box through the gun not long after I bought it but had feeding issues at the time).

The Gander Mountain gunsmith didn't really insinuate that the incident was my fault as he did concede that the ammo may be the issue. His thought was that perhaps some bit of material got into the primer pocket under the primer during the manufacture of the ammo and that may have caused the round to fire before the bolt was fully in battery.

The only other situation that I can think of is that perhaps my gas system should have been readjusted for the Winchester ammo. As I mentioned earlier, I normally shoot Federal ammo in this rifle and thus had last adjusted the gas system for that. I suppose it is possible that the Winchester ammo may have been hotter and thus caused the action to open before the pressure had dropped sufficiently. I find this unlikely, however, because from what I've read, such a problem usually results in the case sticking in the chamber and the bolt either failing to cycle or ripping the rim off of the case.
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Old March 13, 2011, 09:08 PM   #6
Webleymkv
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Pics

As promised, here are some pics of the culprit case (or at least most of it).





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Old March 13, 2011, 09:47 PM   #7
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That's just one, mangled mess. Not that you needed me to state the obvious...
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Old March 14, 2011, 06:18 AM   #8
wogpotter
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Quote:
I assume that it has the same free floating firing pin arrangement that FAL’s have.
The FAL has a spring-loaded firing pin very similar to the FN-49, but neither free float.
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Old March 14, 2011, 08:09 AM   #9
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Not sure why you said your rifle blew up, unless it was just to get everyone's attention.
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Old March 14, 2011, 10:56 AM   #10
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My memory of the FN-49 is a little hazy, but doesn't the bottom curve of the bolt carrier & the tunnel for the firing pin in the bolt carrier prevent a following hammer from contacting the firing pin till it is 99% in battery?
In the FAL, which is a development from the 49, the hammer may follow through, but can't contact the firing pin rear till the bolt has dropped into the locking recess & the carrier moved forward exposing the firing pin.
If I had to guess I'd say high, or defective primer, or jammed pin in the forward position.
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Old March 14, 2011, 01:57 PM   #11
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I have never fired an FN-49, I know Garand shooters all caution against using hunting ammo in the M-1. Try some milsurp FMJ, see if that makes a difference.
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Old March 14, 2011, 04:55 PM   #12
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Strange,one of the gentlemen on surplusriflerorum.com had a similar incident,only his FN49 was an Argentine 308,but it too I believe was Wichester ammunition,white box ,the case imploded similarly to what you have shown in your pictures.
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Old March 14, 2011, 05:57 PM   #13
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Well, first it is NOT a sensitive primer going off from the bolt hitting it. The primer shows a clear firing pin mark. Nor do I think it is a result of firing pn creep, where the inertia of the firing pin causes it to impact the primer. When that happens the primer is usually flattened back out since there is no resistance to the firing pin being forced backward.

The firing pin mark is too clear for that and very obviously the result of a full hammer impact on the firing pin. (That type of firing pin "crater" requires a certain firing pin support and the primer clearly shows that support.)

Further, the firing pin mark is centered, meaning that the cartridge was fully into the bolt face and under the extractor so the bolt had to be around 1" or less from complete closure.

I think that at one point, the bolt or the carrier stopped its forward motion, short of battery, for some reason. The shooter, not realizing the bolt was not fully closed, pulled the trigger. (That gun does not have a disconnector.) Some defect of the gun allowed the hammer to reach the firing pin; the extractor held the case head firmly enough to ensure good support for the case and permit a full firing pin blow. And ka-boom!

The case seems to confirm the above theorizing. The case blew out, but enough was in the chamber that high pressure gas came back around the case, crushing it. The internal pressure meanwhile had blown the head off the case in the classic "excess headspace" condition. There was probably enough pressure to push the bullet out the barrel; the OP doesn't say, but I think he would have mentioned a stuck bullet.

There you have MHO.

Jim
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Old March 14, 2011, 07:52 PM   #14
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I agree about the firing pin impression, what bugs me is the line from the impression over to the edge of the primer!
That looks like the pin was pressed into the primer when the bolt unlocked (or locked) I can't tell which, but I'm favoring locked because of the center hit on the primer cup.
If that's the case we're looking at a gas system malfunction not having enough dwell time before unlocking, or a shot locking shoulder or bolt locking face.
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Old March 14, 2011, 09:11 PM   #15
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I don't think there is premature unlocking, as that is about impossible in a gas gun where the bullet has to reach the gas port to start the unlocking process. I don't think the gun was ever locked, and that somehow the hammer reached the firing pin with the bolt partly open.

I see what you mean about the line, though. It looks like what you might see in a dropping barrel pistol, but the FN-49 bolt doesn't drop at the front. The only way I can see that line happening at the time of firing is if the bolt was actually blown upward or to the side, leaving that mark as the firing pin scraped the cartridge case. What happened to the bolt and bolt carrier? Did they blow out of the gun?

Also can you tell where the extractor was? Those look like extractor scrape marks on the (viewer's) right side of the picture. The extractor position would let us orient the case the way it was in the gun.

A thought, though. One thing that could stop the bolt carrier and the bolt would be the gas piston if it stuck out part way. Can you check to see if it might be bent or have a burr or something that could do that?

Jim
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Old March 15, 2011, 08:57 AM   #16
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You may be right about the extractor, either there or it caused the chunk ripped from the rim a t 6 o'clock? Hard to tell looking at just a fuzzy pic. Is the extractor in a FN-49 in the same orientation as in a FAL?

The only reason I mentioned premature unlocking is that there was an incident a while back with a FAL (as close as I can claim to expertise with an FN-49) where there was a slightly over-length gas piston fitted. There is meant to be a small (1/8" or so) gap between the piston rear face & the bolt carrier front face. this is designed (in a FAL) to create a short delay before contacting the bolt & carrier so that the breech pressure can drop lower before starting the unlocking camming. What that shooter was experiencing was very similar & it took a while to figure out as the difference was so slight it needed measuring to even find it.
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Old March 15, 2011, 02:07 PM   #17
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Good point, wogpotter, and I also thought of a gas port setting too tight, but the problem is that those things would cause a problem on every shot, not the third or fourth. I would like to see that rifle and see if there is a point where the hammer can reach the firing pin with the bolt out of battery. I have been trying it with my 49 and can't get it to do anything wrong, but it does look like some wear might allow contact.

Something like a wrong or incorrectly made (repro?) part cannot really be ruled out after so many years and many hands.

I hate it when something like this happens and the quick glib response is "Oh, they fire out of battery all the time" or something like that. "They" shouldn't, and I like to find out what went wrong, not just talk about floating firing pins that don't float or high primers that aren't high or reloads that aren't reloads.

Jim
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Old March 15, 2011, 03:58 PM   #18
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I know what you mean.
I replaced the 1-piece firing pin in my FAL as they have similar pin breakage issues. After swapping them I had too much FP protrusion with "identically interchangeable" parts! I ended up using a FP protrusion gauge & re-grinding the FP front half's tip, but only after a lot of checking to find where EXACTLY the discrepancy was. Luckily I discovered the problem before there was a problem.
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Old March 15, 2011, 06:26 PM   #19
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Well, first it is NOT a sensitive primer going off from the bolt hitting it. The primer shows a clear firing pin mark.
And how very wrong is the assumption that a slamfire round won't have a nice deep firing pin mark.

I had two out of battery slamfires in Garands, the second blew the receiver heel into my face. Both cases had nice deep firing pin marks. No primer cupping either.

I had one inbattery slamfire with a AR with the new brass finish WSR. The primer mark was indistinguishable from any other round I fired that day, no primer cupping.

And the second shooter on my firing point, he had a AR slamfire, with Federal match, and his primer looked like any fired primer. Nice deep primer mark. no primer cupping.

In a recent Rifle or Handloader magazine, Mike Venturino shows the back end of a 7.62 Russian slamfire case. Not a shallow primer mark, though on his rifle, there is some cupping.

I don't know why this is so, but it is so. Maybe someone can install a high speed camera in the bolt face and figure out the mystery.
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Old March 15, 2011, 08:48 PM   #20
Webleymkv
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Originally posted by Jim Keenan
Quote:
I think that at one point, the bolt or the carrier stopped its forward motion, short of battery, for some reason. The shooter, not realizing the bolt was not fully closed, pulled the trigger. (That gun does not have a disconnector.) Some defect of the gun allowed the hammer to reach the firing pin; the extractor held the case head firmly enough to ensure good support for the case and permit a full firing pin blow. And ka-boom!
I'm not sure if that's possible as, if the gun weren't fully into battery, the hammer should strike the back of the bolt carrier rather than the firing pin. The only way that I can think of that the above scenario might have happened with my rifle is if the hammer striking the bolt carrier went ahead and shoved it the rest of the way forward and struck the firing pin on the way. In that case, however, I'd think that it would also go ahead and push the bolt into battery thus preventing the situation that occurred.

Quote:
The case seems to confirm the above theorizing. The case blew out, but enough was in the chamber that high pressure gas came back around the case, crushing it. The internal pressure meanwhile had blown the head off the case in the classic "excess headspace" condition. There was probably enough pressure to push the bullet out the barrel; the OP doesn't say, but I think he would have mentioned a stuck bullet.
Nope, the bore was clear.

Originally posted by wogpotter
Quote:
I agree about the firing pin impression, what bugs me is the line from the impression over to the edge of the primer!
That looks like the pin was pressed into the primer when the bolt unlocked (or locked) I can't tell which, but I'm favoring locked because of the center hit on the primer cup.
If that's the case we're looking at a gas system malfunction not having enough dwell time before unlocking, or a shot locking shoulder or bolt locking face.
A gas system issue is possible as last time I adjusted the gas system I was using a different brand of ammo (Federal 150grn Power-Shok). I notice from looking at the manufacturers' websites that the Winchester ammo I was using (150grn Power Point JSP) is listed as having a muzzle velocity 10fps higher than the Federal. I suppose it is possible that the Winchester sent more gas through the port than usual and caused the bolt to unlock prematurely. However, in that case I'd think it would be more likely to simply fail to extract and/or tear the rim off the case.

Originally posted by Jim Keenan
Quote:
I see what you mean about the line, though. It looks like what you might see in a dropping barrel pistol, but the FN-49 bolt doesn't drop at the front. The only way I can see that line happening at the time of firing is if the bolt was actually blown upward or to the side, leaving that mark as the firing pin scraped the cartridge case. What happened to the bolt and bolt carrier? Did they blow out of the gun?
No, the bolt and carrier were in their normal channels immediately after the incident.

Quote:
Also can you tell where the extractor was? Those look like extractor scrape marks on the (viewer's) right side of the picture. The extractor position would let us orient the case the way it was in the gun.

A thought, though. One thing that could stop the bolt carrier and the bolt would be the gas piston if it stuck out part way. Can you check to see if it might be bent or have a burr or something that could do that?
I can't really tell where the extractor was on the case. I can tell you however, that if you are looking at the face of the bolt from the front, the extractor is on the upper left-hand side (the rifle ejects up and to the shooter's right). Also the gas pistol was not stuck out immediately after the incident and moves freely as far as I can pull it against its return spring.

Originally posted by wogpotter
Quote:
I replaced the 1-piece firing pin in my FAL as they have similar pin breakage issues. After swapping them I had too much FP protrusion with "identically interchangeable" parts! I ended up using a FP protrusion gauge & re-grinding the FP front half's tip, but only after a lot of checking to find where EXACTLY the discrepancy was. Luckily I discovered the problem before there was a problem.
I have not made any modification to the firing pin since it was installed. However, the pin does not protrude from the front of the bolt unless the rear portion is depressed. Also, I replaced the firing pin return spring with an extra-heavy one after having issues with slamfires before (it would fire 2-3 shots with 1 trigger pull).

Also, I considered maybe a problem with the sear or auxillary sear engagements allowing the hammer to follow. However, none of those engagements appear worn nor was I able to make the hammer follow in messing with it unloaded at home. In order for the bolt to travel rearward enough to feed a new cartridge, it always seems to ride back far enough to re-cock the hammer no matter how I try to manipulate the rifle.
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Old March 15, 2011, 08:54 PM   #21
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Well, Slamfire, I guess I have to bow to expertise as you have had and seen more slamfires than anyone else I have ever known.* But in my much more limited experience, a slamfire with no backup to the firing pin (that is nothing but firing pin inertia) will let the primer internal pressure push the primer metal back out, even into the firing pin hole if the design allows it. It takes a goodly amount of firing pin inertia and case support to get that kind of primer appearance.

The high primer type slamfire is the result of the bolt face hitting the primer; there usually is no firing pin mark at all since the firing pin didn't set off the primer, the bolt face did.

The FN-49 and FAL both have very strong firing pin springs just to prevent firing pin creep and possible slam fires, since the bolt is moving straight forward and no inertia is taken up by the bolt turning.

I still think there is something about that KB we don't know.

*Nine times out of ten when someone says "slamfire" they mean the bolt was locked but the sear jarred off or a light trigger was pulled accidentally, but that certainly is not the situation when a receiver blows apart.

Jim
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Old March 16, 2011, 08:04 AM   #22
wogpotter
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Bear in mind we're just guessing here having not had the actual rifle in our hands. Also bear in mind no-one is "having a go" at you, we're just curious to find a definite answer to what & how this happened.

2 things that come to light from your post.
Firstly that is an abnormally high incidence of incidents.
Secondly there was a change made (the spring).

Based on that I'd guess there is a problem somewhere within the rifle/ammunition/user chain. I don't think it is drastic, but it IS causing incidents so it probably needs fixing for your comfort & safety. Ammo with 10 FPS is very, very minor, but ammo with a different pressure curve from a different propellant may well be causing the gas to behave differently, even if the velocities are identical.
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Old March 16, 2011, 09:42 AM   #23
Webleymkv
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Quote:
Bear in mind we're just guessing here having not had the actual rifle in our hands. Also bear in mind no-one is "having a go" at you, we're just curious to find a definite answer to what & how this happened.
Oh, I never really thought anyone was "having a go" at me, I know you're all trying to help.

Quote:
2 things that come to light from your post.
Firstly that is an abnormally high incidence of incidents.
Secondly there was a change made (the spring).
I'm not overly inclined to think that the spring is the issue as this is the first incident I've had since replacing it. I actually had more slamfires before with the OE spring and I intentionally put in a much heavier spring because of it. Also, I'd shot the rifle a fair amount with Federal ammo after replacing the spring without issue.

Quote:
Based on that I'd guess there is a problem somewhere within the rifle/ammunition/user chain. I don't think it is drastic, but it IS causing incidents so it probably needs fixing for your comfort & safety. Ammo with 10 FPS is very, very minor, but ammo with a different pressure curve from a different propellant may well be causing the gas to behave differently, even if the velocities are identical.
The more I think about it, I think the problem probably has to do with the ammo, gas system adjustment, or both. As I stated earlier, I did have the rifle checked by a gunsmith who seemed fairly familiar with FN-49's and he told me it was mechanically fine. An improper setting on the gas system or defective ammunition, however, wouldn't be something that he would have been able to tell unless he fired the rifle. I'm beginning to think that one needs to adjust the gas system for a specific loading and either stick just to that or readjust the gas system anytime a different ammo is used.

Either way, I'm getting rid of this rifle. Even if it is mechanically fine, I have no use for a gun that I have to be so picky about ammunition with. I feel that I can sell it in good concience since a gunsmith has given it the mechanical OK. I've also opened the gas vent all the way (this allows the least amount of gas to act against the piston) and set the plug to the grenade launching setting (this prevents semi-auto fire) so that whoever I sell it to will have to adjust the gas system for whatever ammo he decides to use.
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Old March 16, 2011, 08:07 PM   #24
James K
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You had more slamfires before? What happened those times and how often have you rebuilt that rifle? There has to be something wrong somewhere.

That is a bit like someone saying he is getting tired of being struck by lightning!

Jim
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Old March 16, 2011, 08:17 PM   #25
frick74
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I sure hope you plan on telling the next owner about your experience with this rifle.

And, one gunsmith, who may or may not have been familiar with the rifle, wouldn't ease my conscience if the next owner got hurt because the problem re-occurred.

I know its a bite in the butt, but, I don't think my conscience could rest very easily after I sold the rifle for anything other than a wall hanger, making dang sure it was disabled from every firing another round again.

And, frankly, I am surprised the Gander Mt. Gunsmith gave you a go ahead to re use the rifle, did you get it in writing? Cause if somebody gets sued, you better have either a no fire letter signed by the buyer, or paperwork covering your butt.

I myself, would torch the dang thing, eat the lost money, and sleep better at night.
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