Full Auto HK-91 Story T/F

A-Mac.50 · December 28, 2006, 08:04 PM

I was reading about the 1997 L.A. bank robbery/shoot-out, and well heres the problem "The detective had been firing at Phillips; one of his rounds, a ricochet, struck the gunman's hand, while another hit the HK-91's trigger group. Instead of disabling the weapon, however, the bullet destroyed the second sear inside the gun, accidentally causing it to become a fully automatic rifle." Can that actualy happen? A bullet damaging the sear and making the gun a full auto? Sounds like BS but I could be wrong.

Thanks for the help, A Mac

oldbillthundercheif · December 29, 2006, 01:50 AM

I think that HK was full-auto to start off with...

I remember one of the guys switched rifles at some point in the action. I think he swithed to the HK after his AK became unservicable for whatever reason... That may have been the rifle that was shot.

I think all of the rifles used by the two dumbasses were full-auto but it's been a while since I have seen that episode of "Shootout" on the history channel.

VUPDblue · December 29, 2006, 08:29 AM

If that were to be true, wouldn't that have caused a single trigger pull to become a mag-dump with no "burst" capability? Oldbillthunderchief might be right on the money too. I think those rifles that were used in that crime were FA to begin with.

M1911 · December 29, 2006, 08:50 AM

When I was at either LFI-1 or LFI-II, Ayoob told the class that his law enforcement sources told him that the HK-91 had been illegally converted to full-auto in Mexico. Dunno if that was true or not, but that is what Ayoob said at the time...

guntotin_fool · December 30, 2006, 02:00 AM

My looking at schematics, show no way that i can see that it would do that, out side of only allowing a mag dump with one trigger pull, then doing nothing the next one.

MDW Guns · December 30, 2006, 11:21 AM

That is not true.
I watched the whole thing on TV when it happend and he took the HK91 out of the trunk and start shooting full auto.

AviatorDave · February 23, 2007, 07:51 PM

Yeah, yeah, it's an old post. No, there's no way that "destroying the secondary sear" could make a semi-HK become full-auto. The secondary sear is what MAKES them full auto. If it did have a secondary sear, then it was already full-auto. Semi-auto guns do not have that secondary sear. 2 things happen when the selector is moved to full-auto - a block to the trigger sear is removed, allowing it to be pulled back further so it won't interfere with the hammer. Then, every time the bolt moves back to the locked position, it pushes a trip lever that releases the secondary sear that releases the hammer. Without the secondary sear, the hammer would be in continuous contact with the bolt head, and might never even develop enough velocity to drive the firing pin into the primer. I've never removed my registered sear and tried to shoot it to see what happenes, so I'm not sure if it will fire or not. I suspect that it will not, because if it would, then sear-less trigger packs would be considered "machine gun conversion devices" by the BATFE, and they are in fact not. It is the sear itself that is the registered machine gun conversion device.

Furthermore, the bolt carrier needs a special ramp to release the trip lever. Full-auto versions have the ramp, semi-auto carriers do not. So if you put a full-auto pack onto a gun with a semi-auto carrier, it would not fire in full-auto, and destroying a sear would not change that. Just more evidence that the rifle was already full auto.

So, while it may be possible that a full-auto trigger pack could still fire full auto without the secondary sear, you can't destroy a required part for full auto function, and then say that the destruction of that part caused it to be full-auto.

I have an MP5 with both an SEF trigger pack, and a 3 round burst pack, and I've taken them apart multiple times, so I'm very familiar with their operation.

December 28, 2006, 08:04 PM	#1
A-Mac.50 Member Join Date: November 12, 2005 Posts: 35	Full Auto HK-91 Story T/F I was reading about the 1997 L.A. bank robbery/shoot-out, and well heres the problem "The detective had been firing at Phillips; one of his rounds, a ricochet, struck the gunman's hand, while another hit the HK-91's trigger group. Instead of disabling the weapon, however, the bullet destroyed the second sear inside the gun, accidentally causing it to become a fully automatic rifle." Can that actualy happen? A bullet damaging the sear and making the gun a full auto? Sounds like BS but I could be wrong. Thanks for the help, A Mac

December 29, 2006, 08:29 AM	#3
VUPDblue Senior Member Join Date: December 18, 2005 Location: Central Indiana Posts: 1,981	If that were to be true, wouldn't that have caused a single trigger pull to become a mag-dump with no "burst" capability? Oldbillthunderchief might be right on the money too. I think those rifles that were used in that crime were FA to begin with. __________________ Silencers have NEVER been illegal !

December 30, 2006, 11:21 AM	#6
MDW Guns Member Join Date: January 31, 2006 Location: Maine USA Posts: 86	That is not true. I watched the whole thing on TV when it happend and he took the HK91 out of the trunk and start shooting full auto. __________________ ARMED MEN ARE CITIZENS UNARMED MEN ARE SUBJECTS NRA, FWR 2711 Check www.mdwguns.com for great deals!

December 29, 2006, 01:50 AM	#2
oldbillthundercheif Junior member Join Date: April 21, 2006 Location: New Orleans Posts: 2,450	I think that HK was full-auto to start off with... I remember one of the guys switched rifles at some point in the action. I think he swithed to the HK after his AK became unservicable for whatever reason... That may have been the rifle that was shot. I think all of the rifles used by the two dumbasses were full-auto but it's been a while since I have seen that episode of "Shootout" on the history channel.

December 29, 2006, 08:50 AM	#4
M1911 Senior Member Join Date: March 28, 2000 Posts: 4,055	When I was at either LFI-1 or LFI-II, Ayoob told the class that his law enforcement sources told him that the HK-91 had been illegally converted to full-auto in Mexico. Dunno if that was true or not, but that is what Ayoob said at the time...

December 30, 2006, 02:00 AM	#5
guntotin_fool Senior Member Join Date: November 18, 2004 Posts: 1,446	My looking at schematics, show no way that i can see that it would do that, out side of only allowing a mag dump with one trigger pull, then doing nothing the next one.

February 23, 2007, 07:51 PM	#7
AviatorDave Junior Member Join Date: February 23, 2007 Posts: 3	Yeah, yeah, it's an old post. No, there's no way that "destroying the secondary sear" could make a semi-HK become full-auto. The secondary sear is what MAKES them full auto. If it did have a secondary sear, then it was already full-auto. Semi-auto guns do not have that secondary sear. 2 things happen when the selector is moved to full-auto - a block to the trigger sear is removed, allowing it to be pulled back further so it won't interfere with the hammer. Then, every time the bolt moves back to the locked position, it pushes a trip lever that releases the secondary sear that releases the hammer. Without the secondary sear, the hammer would be in continuous contact with the bolt head, and might never even develop enough velocity to drive the firing pin into the primer. I've never removed my registered sear and tried to shoot it to see what happenes, so I'm not sure if it will fire or not. I suspect that it will not, because if it would, then sear-less trigger packs would be considered "machine gun conversion devices" by the BATFE, and they are in fact not. It is the sear itself that is the registered machine gun conversion device. Furthermore, the bolt carrier needs a special ramp to release the trip lever. Full-auto versions have the ramp, semi-auto carriers do not. So if you put a full-auto pack onto a gun with a semi-auto carrier, it would not fire in full-auto, and destroying a sear would not change that. Just more evidence that the rifle was already full auto. So, while it may be possible that a full-auto trigger pack could still fire full auto without the secondary sear, you can't destroy a required part for full auto function, and then say that the destruction of that part caused it to be full-auto. I have an MP5 with both an SEF trigger pack, and a 3 round burst pack, and I've taken them apart multiple times, so I'm very familiar with their operation.