Deputy's Rifle Discharges in Patrol Car

[General Geoff]

Say again? I've done some pretty brutal things to M16s with a round in the chamber that didn't go off. I've spent many a month with one in the pipe. Could you explain how/why an AR15 is not designed to be carried with a round in the chamber? Then I suppose, pick the pistol of your choice and explain why it is designed to be carried with a round in the chamber?

I don't understand the logic behind your statement. But I'm absolutely willing to learn.

The AR-15 style rifle has a floating firing pin, which would allow for a discharge if the weapon is dropped or jostled in a certain fashion. It is single action. Just because you've carried it with a round chambered, doesn't mean it's meant to be done.

My sidearm is a Smith & Wesson SW99 (Walther P99 clone). It is designed to be carried with a round chambered, because it is a single/double action firearm with an internal striker and a decocker. Thus, it is carried with the striker decocked. Such a weapon cannot go off if it is dropped or jostled in any way, so long as the trigger is not deliberately pulled back.

The same cannot be said for the AR-15.

 

[siglite]

So what you're saying, is that if the rifle had enough forward velocity and stopped in a rapid enough fashion, the firing pin may strike a primer with enough inertia to crank off a round?

Any idea how hard you have to slam the muzzle on the ground to make that happen? I'm curious.

 

[General Geoff]

It's called a slam fire, and it does happen on (rare) occasion. Especially if you're using ammunition with soft primers.

The likelihood of it happening is very low, but it is possible.

 

[siglite]

I'm aware of slam fires happening. I've never had one happen myself, but enough folks I trust to be knowledgeable about ARs and other semi rifles claim to have had them. And I believe them. But I'm curious how much velocity a rifle has to have (and suddenly be brought to a stop) to get that light little AR firing pin to touch off a primer. I've dropped the bolt forward on an AR thousands of times. Never has the buffer spring generate enough forward velocity to slam-fire.

I don't think I've ever hit a bump in a car that hard. Unless you count the head-on collision with a mini-van I had in... I think '94. But I could be wrong, which is the crux of my question. Just how hard is "that hard." And how do we not know that the light weight of the AR15/M16's firing pin is not a design mechanism to prevent slam-fires. Did Mr. Stoner every comment on that? Has colt? Would Mr. Stoner, Colt, or any military manual concur with this design assessment? Would the same apply to an M14? (believe me, I know ZERO about M14s, so I'm interested in that assessment as well)

I have to wonder if it's fair to state that the AR and other rifles are not designed to be carried with a round in the chamber, or if, perhaps, it's more accurate to state that certain pistols have "extra slam-fire prevention mechanisms."

 

[General Geoff]

The M14 (and semi automatic clones thereof) also has a floating firing pin, and is also susceptible to slam fires.

The entire concept behind the floating firing pin mechanism is that it is a compromise of safety for reliability, simplicity, and economy. A floating firing pin mechanism on a gas operated semi automatic rifle is cheaper, more robust, and more reliable than a mechanism which would utilize a firing pin block or an immobilizer of some sort.

And the only precaution that need be taken to prevent any possibility of a slam fire with such a design is that you carry it with an empty chamber. An elegant solution, really.

 

[Big Boomer]

I bet he is on modified duty! He probably can't hear a damn thing! If from the way they describe it, the muzzle must have been pretty close to his head and in the cab of the cruiser that must have been LOUD!

At least it missed his head and when out the back. "note to self" (do not attempt to mess with loaded firearm while driving down the road.)

 

[Flyboy]

Gen. Geoff, call me crazy, but doesn't the 1911 have a floating firing pin? Are you suggesting that it's unsafe for carry?

 

[TAB]

and that is why there are policys/procedures/protocalls. He didn't fallow them, he needs some time to think about it( as in with out pay)... then lots of what should be remedial fire arms training. If I had my way, he would be paying for the damage to the car/ shop... but thats not going to happen.

 

[buttrap]

He had a round up the pipe and the thing cocked no safety on,reached to stop it rattling in the rack and got the fat thumb on the trigger. Then bigadaboom. He also claimed to not recall the last time he had fired the gun or checked the chamber too. Looks like he is going back to gun 101 too after modified duty.

 

[General Geoff]

Gen. Geoff, call me crazy, but doesn't the 1911 have a floating firing pin? Are you suggesting that it's unsafe for carry?

As far as I know, modern 1911s have firing pin blocks operated either by the grip safety, or the manual safety.

 

[doc2rn]

Yup, he had himself a slam fire. I have seen this with alot of M16A2s. Don't alot of departments get theirs from the referb center?

 

[Wes Janson]

As far as I know, modern 1911s have firing pin blocks operated either by the grip safety, or the manual safety.

Err, Kimber Series II pistols have FP safeties, as do Colt Series 80, but a very significant number of other current-production 1911s, including models from both those companies, omit that "feature".

As I recall, there are a considerable number of people out there in instructing positions who believe that a 1911 should not have an unnecessary safety system that introduces greater potential for mechanical failure.


Perhaps the cartridge in question had been previously chambered several times, and the officer accidentally hit the bolt release, causing a slamfire?

 

[TAB]

Perhaps the cartridge in question had been previously chambered several times, and the officer accidentally hit the bolt release, causing a slamfire?

then that begs the question, why was the action open and a mag inserted?( forget the whole safety factor...From a tactical stand point thats very bad... I can't see any agency allowing that.)

So at the very least he was still violating protocall, that resulted in a a NA. How is that diffrent from him reaching back and hitting the trigger making it go bang?

 

[Run&Shoot]

This is in no way a slam fire. A slam fire is when the bolt is pulled back and release under the spring pressure. A floating firing pin will continue forward and often dimple the primer but not have enough force to ignite it. He was simply trying to secure it, so he probably pulled the trigger by mistake. No way he pulled the charging handle back and let it snap forward. Even then it would be very unlikely that an AR15 would slam fire. That only happens if the primer is too high or too sensitive or the firing pin is too long.

 

[DoubleTapDrew]

No way he pulled the charging handle back and let it snap forward.

Or hit the bolt release. But I agree. The story says (although poorly worded) there was a "bullet in the barrel" so I'm pretty sure he hit the trigger.

 

[dmazur]

Regarding floating firing pins -

From experience with the Garand (which I believe has a very similar bolt and trigger mechanism to the M14), there is a "bridge" in the receiver and the end of the trigger is L-shaped to engage this. This serves as a firing pin block until the bolt rotates and engages its lugs, rotating the firing pin with it. Garand included this design element deliberately. What can happen is that things wear. The bridge and "L" wear, and the result can be a slam-fire. But a rifle with parts to specification makes no impression (or a very small one) on the primer when the bolt slams closed. The concern over slam-fires with M1's and M14's is largely due to the indeterminate age of the parts, many of which are 60 years old.

From experience with the 1911 (including both the model with a firing pin safety and the model without), the design includes a firing pin spring. So, it really can't be described as floating. Testing showed that if a 1911 with a round chambered was dropped onto concrete from a height of 4 ft, it could fire if it landed on its muzzle. The result was the somewhat unfortunate complication of a perfectly good design with firing pin safeties. For completeness, it should be noted that a combination of a lighter firing pin (titanium) and a heavier firing pin spring has created a modification that passes the 4 ft drop test, if I have my facts correct.

There are endless debates on what condition of readiness is correct for 1911 carry, so I won't try to reopen that. I am also aware of similar debates on the wisdom of carrying a rifle with a round chambered while hunting. So, I'm not surprised that there are similar concerns for law enforcement.

I personally subscribe to Condition 3. (Magazine in, slide activation required to chamber a round) However, I'm not living in a combat zone or responding to a felony call.

I would venture an opinion that the transition between "carrying hot" and "carrying cold" should be dictated by circumstances, and that individuals exercise diligence to verify "cold" instead of assuming that the weapon was returned to that status.

 

[Drail]

Perhaps police administrations should consider spending more less time writing speeding tickets and more time on weapon safety. Riding around in a vehicle with a hot weapon in an overhead rack IMO is totally unnecessary. How many seconds does it take to chamber a round into a rifle that is presumably locked into a rack with the muzzle pointing out of the vehicle. I wonder how many departments follow this example.

 

[Wes Janson]

Well, 99.9% of departments/officers don't seem to have a problem figuring out the concept of "cruiser-safe". It's always that same .1% though...

 

[ilbob]

Gen. Geoff, call me crazy, but doesn't the 1911 have a floating firing pin? Are you suggesting that it's unsafe for carry?

There have been a number of cases where a loaded 1911, even on safe, discharged when dropped. Its not real common, but it has happened, because the original design does not include a firing pin block.

 

[MechAg94]

I have never seen a slam fire on any AR I have used. In fact, the two AR's I have shot will not chamber a round reliably unless you allow the bolt to slam forward. Letting it forward slowly doesn't work well.

Just to clarify what I saw above, a slam fire is NOT when you slam the muzzle into the ground. That is not the same as slamming the bolt home.


IMHO, this officer probably didn't bother to inspect the rifle before using the vehicle. When he heard it rattling, he reached behind him while driving and accidentally hit the trigger on the loaded and ready-to-fire rifle. I bet the rifle had be loaded for quite some time.

 

[ilbob]

DoubleTapDrew

The report read that the bullet tore through the headliner and then out of a rear window. That means it was pointed upward, right?

I didn't see any pics but I have seen mounts now for ARs that mount it crosswise on the headliner, just above and behind the front seats. I assume that's what this was.

Would seem to violate rule 1.

 

[pbearperry]

What a Cop made a mistake?Get the rope boys,we are gonna have a necktie party.

 

[kd7nqb]

from ride alongs and other interactions I have done all the AR's and shotguns are secured vertically. I also notice that many times although not all the time the vertical line is directly under the light bar. This seems like it may be an added piece of protection by adding more "stuff" for an ND to go through. Although a good .223 round might not have any issue at all penetrating the roof liner, roof and light bar mount.

Also its my belief that policy in my neck of the woods is to keep a full mag in the gun but no rounds in the chamber.

Finally would the sound of an AR going off in an enclosed vehicle be enough to break a window? Would he have lasting hearing damage?

 

[shooter429]

First if all, no "big deal?"

I was surprised when the news started showing up because I didn’t think it was a big deal,

Is this guy kidding? Nobody was hurt this time, but I hardly think officer/deputy having a possible NDs is no big deal. Sounds like they need to increase training time and vigilance. Once as a new CO on perimeter patrol we had an officer who had an ND. The sergeant pulled us off patrol one by one and went over protocols and safe gun handling right then and there. There were memos and and training and all sorts of "reminders" for quite a while after that (of course that officer had shot himself). Sorry, but it is a big deal, because someone could have died (including the Deputy).

Anyway, keep in mind that not all LEOs are gun enthusiasts. Train and practice practice practice. Maybe they will get some more training time now.

Shooter429

 

[waterhouse]

We always put all long guns in the vehicles "Cruiser Ready." Part of the training was showing a picture of a sedan with some nice holes in the roof from an Agent who didn't do this and hit a bump (that was an 870).

In most cases they were locked in place anyway, so the extra half a second to operate the slide, was pretty meaningless compared to getting the key and unlocking it in the first place.

I'm not sure how they all work, but ours were mounted in between the front seats, facing up, and the lock system had a button on the instrument panel (where the lights, sirens, etc. are controlled from) that you pushed to unlock the long arm. Hit the button, grab the gun, and go. It was very quick.

I am a fan of having a rifle or shotgun available to patrol officers, but it probably would be best if it is secured in the trunk unless needed.

If you really need it, you want it right next to you, not in the trunk. While the SWAT team might get a call and have time to gear up on the way to the scene, the guy out in his marked sedan might need to get to his long arm right away.