MP5 full auto questions

ROFOCALE · January 8, 2009, 03:26 AM

I have a few questions on (not the legality) but the possiblity in theory of course of making a semi MP5 clone full auto.

If all the necessary full auto parts are in the trigger pack. what stops someone from purchasing a f/a trigger pack and swapping it into a semi auto?

i have read on a few websites something about it needs to have a hole drilled in the receiver to accept the f/a trigger pack. and just the hole drilled in the receiver will make it a machine gun according to BATFE.

then something about the trigger pack housing can be cliped and pinned in order to attach the f/a trigger housing to a semi auto. if the pack can be cliped and pinned to attach to a semi auto. keeping the orginal internal parts in the f/a pack unmodified to semi would make it f/a? or is the f/a sear not included in a trigger pack internal parts or is it placed somewhere else on the receiver?

If anyone can also refer to me to a detailed book about the MP5 semi and f/a internals and the differences?

questions are just for pure curiousity on the differences of the semi and f/a MP5.

Rofocale

MisterPX · January 8, 2009, 11:06 AM

Get a FA lower, and a FA bolt carrier. THat and some cutting can make you a felon in these United States.

GE-Minigun · January 8, 2009, 02:30 PM

Can’t help with the HK stuff, however the FA trigger/group pack is like the DIAS for the AR15. You take out the trigger group of your semi and install the FA trigger and be good to go, after all the FA trigger group IS the machine gun and not the gun itself, just like the DIAS’s and LL’s. As to drilling the receiver and pinned and recessed…no idea.

Chipperman · January 8, 2009, 06:13 PM

Quote:

after all the FA trigger group IS the machine gun and not the gun itself,

Actually for some HK's the receiver is the machine gun, not the sear.

ROFOCALE · January 8, 2009, 09:49 PM

So if some HK receivers are classified as machine guns. Is this because the receiver has the ability to accept a fa trigger pack?

Hkmp5sd · January 8, 2009, 09:59 PM

Quote:

Actually for some HK's the receiver is the machine gun, not the sear.

What are you calling the "receiver"? On the HK, the registered part is the trigger pack or the sear. You can take the trigger pack from a registered MP5, put it on a HK SP-89 and make it a HK MP5K.

My registered sear is "married" to my trigger pack (the trigger pack has a serial number that is shown on my Form 4 as to where the sear is currently installed). My receiver (the upper half) is registered as a short barreled rifle/suppressor on a single tax stamp.

Quote:

Is this because the receiver has the ability to accept a fa trigger pack?

Any receiver will accept the full auto trigger pack.

David Hineline · January 8, 2009, 10:25 PM

Factory HK machineguns take a swing down full auto trigger housing and fire control group. There are very few original transferable HK machineguns in circulation and most people are not around LE/Govment factory machineguns.

What most have is some type of a semi auto gun that has been converted somehow to fire in fully automatic.

A semi auto gun if you drill the receiver to accept the unregistered machinegun factory pack, you have just created a machinegun receiver by modifying the receiver to accept a machinegun pack which is just a spare part and not registered. This was one way to make a transferable machinegun before 1986, these are called registered receiver conversion machineguns and they accept all factory unregistered spare parts trigger groups and select fire packs.

This was not the most common conversion method because you ended up with one machinegun. The more common method was to modify a semi auto clip on trigger pack to operate in the fully automatic mode with a registered conversion sear, this way you have not changed the legal status of the host semi auto weapon, but have created a conversion device that can go hippety hoppety to any semi auto HK type firearm. MP5 to HK21 beltfed.

Some people needed to have HK pictogram lowers, and 4 position and 2 shot burst groups so they could be more tactical than thier friends. This required taking a factory swing down lower, cutting it up and making the housing into a clip on lower and then putting a registered trigger group or registered sear into this decorative machinegun housing.

If you goto http://www.hkpro.com and look for the HK conversion artical by Tom Hoel it explains the ways all the conversions were done.

Hkmp5sd · January 8, 2009, 11:03 PM

Ah, now I think I understand.

So if you have a registered receiver conversion, you cannot legally take your trigger pack (mainly because it would not work without modifying the receiver) and move it to another gun, but with the registered sear conversion, you can?

ROFOCALE · January 9, 2009, 04:51 AM

So basically in theory.

One can A. convert a semi auto receiver to accept a f/a trigger pack?

B. convert a f/a trigger pack to be mounted on a semi auto receiver?

Now would it be possible to place a f/a trigger assembly into a semi auto trigger housing without mods? also how can a f/a sear be placed into a semi auto trigger assembly?

David Hineline · January 9, 2009, 10:34 AM

Ah, now I think I understand.

So if you have a registered receiver conversion, you cannot legally take your trigger pack (mainly because it would not work without modifying the receiver) and move it to another gun, but with the registered sear conversion, you can?

In the general sense of normalicy the above would be correct, but remember before 1986 people could do these conversions at home. Some home workshop goob could have registered the receiver but modified the semi auto trigger pack. So even though this gun is a registered receiver gun on paper one can not drill the receiver for a push pin swing down factory lower now because that leaves in existance a modified semi auto to full auto trigger group which is a machinegun conversion device unregistered creating a second machinegun.

When shopping one really needs to know what they are buying. So always a good idea when buying non factory machineguns to ask the experts on that gun the pros and cons.

David Hineline · January 9, 2009, 10:38 AM

So basically in theory.

One can A. convert a semi auto receiver to accept a f/a trigger pack?

B. convert a f/a trigger pack to be mounted on a semi auto receiver?

Now would it be possible to place a f/a trigger assembly into a semi auto trigger housing without mods? also how can a f/a sear be placed into a semi auto trigger assembly?

Topic A before 1986 anyone could do this with proper ATF paperwork, after 1986 this can only be done for LE/Govment usage. Penalties for possesion of illegally converted post 86 machinegun is up to $250,000 fine and up to 10yrs in prison, but minimum you will never own a gun or vote again as a conviceted felon.

Topib B Yes this can/could be done before 1986 see above response.

If you had a semi auto HK style weapon now and you want to legally convert it, you would have to buy an ATF registered transferable sear/trigger pack conversion set and pay the going rate of $13,000 for such an item. There is no free lunch program in regards to machineguns anymore.

ROFOCALE · January 10, 2009, 01:03 AM

So there is no necessary parts needed in the receiver to make a semi f/a?
The bolt carrier doesn't need to be changed ? I can purchase a semi auto clone and registered fa pack modify pack to fit semi auto receiver and no other parts ate necessary.

David Hineline · January 10, 2009, 04:18 AM

There is a trip surface on the factory HK semi auto guns that was ground off, this surface can be welded back on or a machine gun bolt carrier can be dropped in.

Also different caliber guns had different ejectors and hammer springs in the trigger pack so when you move the trigger pack from say a 9mm to a .223 to a .308 then the ejector needs be swapped out.

AK103K · January 10, 2009, 01:02 PM

My MP5 was a registered receiver gun done by Fleming just before the ban. It had the standard semi auto trigger housing (no third hole and the "shelf" in the gun was unaltered), but the trigger group was modified (a cut to the group itself so it would clear the "shelf" in the receiver) to work in the "basically" unaltered semi auto gun. The barrel was also cut to the standard MP5 length and not replaced.

A boy I used to shoot with on a regular basis back in the 90's had an HK factory converted 94 to MP5. Supposedly it was one of only a very few ever done here by HK prior to the ban. I never understood why he was shooting it for what its probably worth. He had other conversions too, so it wasnt his only gun. It was a very nice gun though, and there was no telling it from a standard MP5.

While I had mine for over 20 years (shot the scheiße out of it too.

), I sold it last year as things started looking bad, and prices were pretty much at their peak. Looks like I made a good choice, as the prices I've seen recently seem to be slipping, and at the last show I was at, they were asking on the tables not much more than I got selling directly to a dealer last year. I only paid $450 for the HK94 and $350 for the conversion back in 86, and the thought of loosing all that equity in the gun at the stroke of a pen was a deciding factor. No real regets either, other than a some sentimental. My kids learned to shoot full auto on that gun, and we all had a lot of fun with it.

I think I'm going to go into the "prophecy" business. I cashed out my 401K the Friday before the big Monday crash. My wife didnt and is REALLY pi$$ed. She also wants to know if I have any more MP5's in the safe to sell.

I think I saw Carnac the Magnificent's turban on EBay the other day. Might could have to pick that up.

ROFOCALE · January 12, 2009, 02:39 AM

thank you for the all the good info. is there any good books you can recommend about the MP5? Like on the tear down of the gun etc...

aroundlsu · January 12, 2009, 12:38 PM

This is the definitive mp5 book:

http://www.amazon.com/Heckler-Kochs-.../dp/0937752150

I thought I knew everything about the mp5 until I got this book.

January 8, 2009, 03:26 AM	#1
ROFOCALE Member Join Date: January 8, 2009 Posts: 21	MP5 full auto questions I have a few questions on (not the legality) but the possiblity in theory of course of making a semi MP5 clone full auto. If all the necessary full auto parts are in the trigger pack. what stops someone from purchasing a f/a trigger pack and swapping it into a semi auto? i have read on a few websites something about it needs to have a hole drilled in the receiver to accept the f/a trigger pack. and just the hole drilled in the receiver will make it a machine gun according to BATFE. then something about the trigger pack housing can be cliped and pinned in order to attach the f/a trigger housing to a semi auto. if the pack can be cliped and pinned to attach to a semi auto. keeping the orginal internal parts in the f/a pack unmodified to semi would make it f/a? or is the f/a sear not included in a trigger pack internal parts or is it placed somewhere else on the receiver? If anyone can also refer to me to a detailed book about the MP5 semi and f/a internals and the differences? questions are just for pure curiousity on the differences of the semi and f/a MP5. Rofocale

January 8, 2009, 10:25 PM	#7
David Hineline Senior Member Join Date: December 23, 1999 Location: South Sioux City, Nebraska Posts: 704	People speak when they should listen Factory HK machineguns take a swing down full auto trigger housing and fire control group. There are very few original transferable HK machineguns in circulation and most people are not around LE/Govment factory machineguns. What most have is some type of a semi auto gun that has been converted somehow to fire in fully automatic. A semi auto gun if you drill the receiver to accept the unregistered machinegun factory pack, you have just created a machinegun receiver by modifying the receiver to accept a machinegun pack which is just a spare part and not registered. This was one way to make a transferable machinegun before 1986, these are called registered receiver conversion machineguns and they accept all factory unregistered spare parts trigger groups and select fire packs. This was not the most common conversion method because you ended up with one machinegun. The more common method was to modify a semi auto clip on trigger pack to operate in the fully automatic mode with a registered conversion sear, this way you have not changed the legal status of the host semi auto weapon, but have created a conversion device that can go hippety hoppety to any semi auto HK type firearm. MP5 to HK21 beltfed. Some people needed to have HK pictogram lowers, and 4 position and 2 shot burst groups so they could be more tactical than thier friends. This required taking a factory swing down lower, cutting it up and making the housing into a clip on lower and then putting a registered trigger group or registered sear into this decorative machinegun housing. If you goto http://www.hkpro.com and look for the HK conversion artical by Tom Hoel it explains the ways all the conversions were done.

January 9, 2009, 04:51 AM	#9
ROFOCALE Member Join Date: January 8, 2009 Posts: 21	still more questions So basically in theory. One can A. convert a semi auto receiver to accept a f/a trigger pack? B. convert a f/a trigger pack to be mounted on a semi auto receiver? Now would it be possible to place a f/a trigger assembly into a semi auto trigger housing without mods? also how can a f/a sear be placed into a semi auto trigger assembly?

January 12, 2009, 02:39 AM	#15
ROFOCALE Member Join Date: January 8, 2009 Posts: 21	thanks david thank you for the all the good info. is there any good books you can recommend about the MP5? Like on the tear down of the gun etc...

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January 8, 2009, 11:06 AM	#2
MisterPX Senior Member Join Date: April 25, 2006 Location: Amerika's Doyleland Posts: 809	Get a FA lower, and a FA bolt carrier. THat and some cutting can make you a felon in these United States.

January 8, 2009, 02:30 PM	#3
GE-Minigun Senior Member Join Date: September 26, 2008 Posts: 240	Can’t help with the HK stuff, however the FA trigger/group pack is like the DIAS for the AR15. You take out the trigger group of your semi and install the FA trigger and be good to go, after all the FA trigger group IS the machine gun and not the gun itself, just like the DIAS’s and LL’s. As to drilling the receiver and pinned and recessed…no idea.

January 8, 2009, 09:49 PM	#5
ROFOCALE Member Join Date: January 8, 2009 Posts: 21	So if some HK receivers are classified as machine guns. Is this because the receiver has the ability to accept a fa trigger pack?

January 8, 2009, 11:03 PM	#8
Hkmp5sd Senior Member Join Date: December 15, 2001 Location: Winter Haven, Florida Posts: 4,303	Ah, now I think I understand. So if you have a registered receiver conversion, you cannot legally take your trigger pack (mainly because it would not work without modifying the receiver) and move it to another gun, but with the registered sear conversion, you can?

January 9, 2009, 10:34 AM	#10
David Hineline Senior Member Join Date: December 23, 1999 Location: South Sioux City, Nebraska Posts: 704	Ah, now I think I understand. So if you have a registered receiver conversion, you cannot legally take your trigger pack (mainly because it would not work without modifying the receiver) and move it to another gun, but with the registered sear conversion, you can? In the general sense of normalicy the above would be correct, but remember before 1986 people could do these conversions at home. Some home workshop goob could have registered the receiver but modified the semi auto trigger pack. So even though this gun is a registered receiver gun on paper one can not drill the receiver for a push pin swing down factory lower now because that leaves in existance a modified semi auto to full auto trigger group which is a machinegun conversion device unregistered creating a second machinegun. When shopping one really needs to know what they are buying. So always a good idea when buying non factory machineguns to ask the experts on that gun the pros and cons.

January 9, 2009, 10:38 AM	#11
David Hineline Senior Member Join Date: December 23, 1999 Location: South Sioux City, Nebraska Posts: 704	So basically in theory. One can A. convert a semi auto receiver to accept a f/a trigger pack? B. convert a f/a trigger pack to be mounted on a semi auto receiver? Now would it be possible to place a f/a trigger assembly into a semi auto trigger housing without mods? also how can a f/a sear be placed into a semi auto trigger assembly? Topic A before 1986 anyone could do this with proper ATF paperwork, after 1986 this can only be done for LE/Govment usage. Penalties for possesion of illegally converted post 86 machinegun is up to $250,000 fine and up to 10yrs in prison, but minimum you will never own a gun or vote again as a conviceted felon. Topib B Yes this can/could be done before 1986 see above response. If you had a semi auto HK style weapon now and you want to legally convert it, you would have to buy an ATF registered transferable sear/trigger pack conversion set and pay the going rate of $13,000 for such an item. There is no free lunch program in regards to machineguns anymore.

January 10, 2009, 01:03 AM	#12
ROFOCALE Member Join Date: January 8, 2009 Posts: 21	So there is no necessary parts needed in the receiver to make a semi f/a? The bolt carrier doesn't need to be changed ? I can purchase a semi auto clone and registered fa pack modify pack to fit semi auto receiver and no other parts ate necessary.

January 10, 2009, 04:18 AM	#13
David Hineline Senior Member Join Date: December 23, 1999 Location: South Sioux City, Nebraska Posts: 704	There is a trip surface on the factory HK semi auto guns that was ground off, this surface can be welded back on or a machine gun bolt carrier can be dropped in. Also different caliber guns had different ejectors and hammer springs in the trigger pack so when you move the trigger pack from say a 9mm to a .223 to a .308 then the ejector needs be swapped out.

January 10, 2009, 01:02 PM	#14
AK103K Senior Member Join Date: May 1, 2001 Posts: 10,223	My MP5 was a registered receiver gun done by Fleming just before the ban. It had the standard semi auto trigger housing (no third hole and the "shelf" in the gun was unaltered), but the trigger group was modified (a cut to the group itself so it would clear the "shelf" in the receiver) to work in the "basically" unaltered semi auto gun. The barrel was also cut to the standard MP5 length and not replaced. A boy I used to shoot with on a regular basis back in the 90's had an HK factory converted 94 to MP5. Supposedly it was one of only a very few ever done here by HK prior to the ban. I never understood why he was shooting it for what its probably worth. He had other conversions too, so it wasnt his only gun. It was a very nice gun though, and there was no telling it from a standard MP5. While I had mine for over 20 years (shot the scheiße out of it too. ), I sold it last year as things started looking bad, and prices were pretty much at their peak. Looks like I made a good choice, as the prices I've seen recently seem to be slipping, and at the last show I was at, they were asking on the tables not much more than I got selling directly to a dealer last year. I only paid $450 for the HK94 and $350 for the conversion back in 86, and the thought of loosing all that equity in the gun at the stroke of a pen was a deciding factor. No real regets either, other than a some sentimental. My kids learned to shoot full auto on that gun, and we all had a lot of fun with it. I think I'm going to go into the "prophecy" business. I cashed out my 401K the Friday before the big Monday crash. My wife didnt and is REALLY pi$$ed. She also wants to know if I have any more MP5's in the safe to sell. I think I saw Carnac the Magnificent's turban on EBay the other day. Might could have to pick that up.

January 12, 2009, 12:38 PM	#16
aroundlsu Senior Member Join Date: December 7, 2007 Location: Louisiana Posts: 156	This is the definitive mp5 book: http://www.amazon.com/Heckler-Kochs-.../dp/0937752150 I thought I knew everything about the mp5 until I got this book.