posted 05-29-2001 14:30               

quote:

---

Originally posted by jcotter:
However NFA Firearms are not subject to import ban laws. So if you register your rifle as an SBR you would not have to replace import parts with US made parts.

---

I think there's a little confusion over what an NFA weapon is. There are actually different classifications of NFA firearms. If you register a gun as an SBR (which is what I'm doing with my G3KA3) then the only thing you can do is chop the barrel. You still have to abide by the assault weapon ban (no retractable stock or flash surpressor) and you still have to have no more than 10 foreign made parts. If you register the gun as a machinegun then you don't have to deal with either of these restrictions. Of course if you're going the machinegun route you're talking about dropping around $4000 for a registered sear. Remember though, if you have a true HK51 sear gun with the 10" barrel, and decide to have some "full auto" fun with another HK you have by swapping lowers, you CANNOT put the semi trigger pack from the other gun on the 51 or you will be making an unregistered SBR! The only other way to beat the assault weapon ban and 10 parts restrictions without doing the sear gun thing is to start out with a preban gun. Now that everything's as clear as mud, good luck!!!

------------------
Knowledge is power and truth is freedom!

posted 05-29-2001 16:08               

To all who have given input, ***THANKS***. To those who are holding back, :OP

posted 05-29-2001 17:38               

Your point is valid until you state the
fallacy of putting a semiauto pack on a machine gun makes it an illegal SBR. That is FALSE...UNLESS you have a transferable sear that is NOT tied to the gun. The fact is that most G3 (HK51) sears were tied to the serial # of the gun. That makes them BOTH machine guns and you can put a semiauto pack on her if you would like.

If you register a PRE-BAN weapon as a SBR, you cna do more than just cut down the barrel. It is pre-ban...meaning that a retractable stock and flash-hider are OK. However, if you take a FMP receiver that you JUST purchased from Century Arms and register it as SBR, you are limited to the stock and muzzle activity!

Also, if your SBR is a pre-ban gun, you are allowed to disregard the 992 ban from the ATF. You need NO US parts if it a tride and true pre-ban. Example...Say that I take my HK91 and make it a HK51 SBR...The gun was a pre-ban gun, why in the hell would I put and shitty US parts in her? NOT NECESSARY. ONLY on the post-ban stuff, or poorman's SBR's! I have a post-ban HK51 and I registered it as a SBR. I have an American trgger, hammer, sear, stock, carrier (chopped of coarse) and trigger housing. I comply due to the 3 peices of the stock that are US made. I also have a HK51 SBR that I took a sear off of. It is ALL HK and was originally a HK91. the sear was mated to the gun and I seperated them and paid 2 taxes. I have a semiauto pack on it and it is perfectly LEGAL!

Your other misconception is that the sear will work with all other HK's. This is NOT true. The tripp lever needs to be changed and the gun needs to be properly timed. You don't just put a sear in it and have it work. If it were that easy, I would have all my HK's machine guns. It can take up to 5 hours to properly time a HK to assure that it fires in a proper battery.

High Order, I AM BACK! I WILL email you those specs when I get them off of my guns. I have been VERY busy for the past month or so, but I will be a regular again.

Sorry about the LONG post...just wanted to straighten out the misconceptions!

posted 05-29-2001 18:35               

quote:

---

Originally posted by usp40:
Nordic,

Your point is valid until you state the
fallacy of putting a semiauto pack on a machine gun makes it an illegal SBR. That is FALSE...UNLESS you have a transferable sear that is NOT tied to the gun.

---

USP40, looks like you know more about this than myself. Here's some more questions for you then. It was my understanding that the sear itself that was considered a "machinegun" and therefore whatever gun you put the trigger pack on became the "machinegun." That way you could move the lower from gun to gun and be legal. I take it this is what you mean by a transferable sear. My question then is how do you designate a sear as a "transferable sear?" Is it already classified this way, or is it something you do when filling out the paperwork? If it is in fact how you do the paperwork then what is the benefit of having a sear tied to the gun other than being able to put a semi trigger pack on it?

quote:

---

If you register a PRE-BAN weapon as a SBR, you can do more than just cut down the barrel. It is pre-ban...meaning that a retractable stock and flash-hider are OK. However, if you take a FMP receiver that you JUST purchased from Century Arms and register it as SBR, you are limited to the stock and muzzle activity!

---

This is what I meant by saying the two ways to beat the assault weapon ban and the 10 parts rule was to either start with a preban gun or build it from a kit and register it as a machinegun. If you do it either of these ways you can have the retractable stock and flash surpressor. This is correct, right? Here's another question then. Let's say you build it from a kit so it's a post ban gun, but you have a "transferable sear" in it so you can have a flash surpressor and a retractable stock because now it's a machinegun. Next you replace the trigger pack with a semi because you want to "rock" with another of your 91s. Even if being an SBR isn't an issue, it would still be illegal because you would have preban features on a postban gun since it is no longer a "machinegun." Correct?

quote:

---

Your other misconception is that the sear will work with all other HK's. This is NOT true. The tripp lever needs to be changed and the gun needs to be properly timed. You don't just put a sear in it and have it work. If it were that easy, I would have all my HK's machine guns. It can take up to 5 hours to properly time a HK to assure that it fires in a proper battery.

---

Okay, I'm obviously way outa' my leage here. I didn't know that the tripp had to be timed. Is this just for different calibers, or would you have to time it differently for a full-sized G3 vs. a 10" 51 as well?

Here I am thinking that I've learned so much and now you have to come and make me feel like a rookie all over again! HA! Oh well, at least I'm learning. Thanks USP40!

------------------
Knowledge is power and truth is freedom!

posted 05-30-2001 03:00               

Transferable means that anyone can own them. They are NOT dealer samples and are ALSONOT ORIGINAL! What that means is that they are all sear guns. A REAL HK uses a roller sear...a transferable HK uses a friction sear made by someone like Flemming or S&H. The sears (either roller or friction) will fit into any trigger pack with some modification. Basic point...transferable is a clone.

Tying a sear to a gun places you in the hole. You are NOT supposed to switch the pack between guns and it is supposed to remain on the SBR. It is also worth a LOT less $$$$! People want HK sears that can float between their guns.

By putting a sear into a gun..it does NOT constitute a machine gun. The transferable sear is registered and not your HK94 or 93. When someone checks you paperwork, they will find a number that is NOWHERE on the gun. That is becasue it is the sear's serial #.

quote:

---

This is what I meant by saying the two ways to beat the assault weapon ban and the 10 parts rule was to either start with a preban gun or build it from a kit and register it as a machinegun. If you do it either of these ways you can have the retractable stock and flash surpressor. This is correct, right? Here's another question then. Let's say you build it from a kit so it's a post ban gun, but you have a "transferable sear" in it so you can have a flash surpressor and a retractable stock because now it's a machinegun. Next you replace the trigger pack with a semi because you want to "rock" with another of your 91s. Even if being an SBR isn't an issue, it would still be illegal because you would have preban features on a postban gun since it is no longer a "machinegun." Correct?

---

NO. Your sear is the registered part. UNLESS you mate the gun and sear, you will have to follow 992.

quote:

---

Okay, I'm obviously way outa' my leage here. I didn't know that the tripp had to be timed. Is this just for different calibers, or would you have to time it differently for a full-sized G3 vs. a 10" 51 as well?

---

Oh hell yeah you need to time it. The 51 has such a shorter cycle to her...it gets all messed up when it is just placed there.

posted 05-30-2001 03:23               

First off, say I'm shopping for a sear. Does the sear already have some kind of paperwork that says it needs to be tied to a specific gun? Also, you said that these kinds of sears (that are mated to the gun) cost a lot less. How much less are we talking about?

Second question. As far as timing the trip, say I have a SP89, a 94, a 93, and a 91. What you're saying is that there is NO way I can swap a sear triggerpack between guns (even if it's legal) because it simply wouldn't work unless I wanted to spend the effort to re-time it each time I switched guns, correct? So unless you have a number of HKs that are all the same model, why would you need a sear that can be moved between guns?

Final question. Can a friction sear be made to work with trigger packs that include 2-round burst, 3-round burst, etc., or is it only possible to set it up as safe/single/full only?

Thanks again for the free "HK tutorial!" I feel like I'm gettin' smarter by the minute! (Though my wife still thinks this is all an utter waste of time. Oh well...)

------------------
Knowledge is power and truth is freedom!

posted 05-30-2001 18:09               

In a HK sear...
You need to change the tripps between the 91 and the 93/mp5. They are completely different!
They NEED to be timed. You can NOT just swap them out..as much as it makes sense to do so. HK33k IS wrong in stating that they just switch out and complt with each other. I have the proof to verify my claims!

A sear that can be moved between guns is cool because you can have several full autos. What you HAVE to do is make the carriers Full auto though. There is a difference between full auto and semi auto carriers. The trip cut is the MAIN difference. It has to be precise and timed! This requires some work and patience. Any class 2 mfr knows this info!

The rigger pack that are the "pictograph" lowers can work. Have Terry Dyer convert them to accept a transferable (friction) sear and they will be fine. He charges @ $600 a pack, but with the conversion...it is worth it! Then you just place the sear in her and run them! (After the gun is timed and has a sear (trip) cut in the carrier!)

Good luck and if more info is needed, I am here!

posted 05-30-2001 20:23               

/b The 51 has such a shorter cycle to her...it gets all messed up when it is just placed there. /#b

Does this apply to the semi auto version, too? I was wondering if shortening the front of the bolt carrier lightened the weight till it affected the normal cycling. When you say shorter, does that mean that the bolt group actually travels less in a 51 than a 91???

posted 05-31-2001 02:30               

Villuj_Idiot,

That is interesting. Do you have FACTORY HK carriers? If so, there is minimal timing involved. If they are semi's made into full...there is much work needed. Alos, there are 2 distinct differences between the 223 and the 308 tripps. They are no where close to eachother. It is the same with the ejectors. One is longer and thcker than the other. As far as not timing your guns...I think that it is great! I would prefer to just swap out trigger components and rock-N-roll! The fact remains, I have NEVER been able to do so. I have 5 HK full autos and not one sear in interchangeable. The MP5 (S&H Sear) works with my MP5K (Flemming Sear), but it jamms a LOT due to the timing problem. When the Flemming Sear is put back in, the gun runs flawlessy...and vise versa.
BOTH of those guns have FACTORY HK carriers and picto. burst lowers on them.
Killerkain's HK33 has never run since he has had it. He sent it to Gravitt and Jim has had it for the past 6 months! He says that it is all out of time and he has to retime it and make it into a 53...while he has it...but that gun came straight from Flemming. The hack job that they do...

posted 05-31-2001 07:28               

People talk about Fleming's "hack jobs", but I've only seen good work from his shop. Everything I've owned or fired that was made by him always worked.

posted 05-31-2001 18:06               

Timing is easiest to adjust by adding a little weld to "point" of release lever (where it contacts carrier) then file back to shape. Idea is to have it release sear just before carrier is full forward. Too far forward before release, the gun gets cranky. Release way too soon and it may not fire at all, or even worse, fire before bolt is locked. USE CAUTION! Be conservative.

Shape of ramp in carrier that contacts release lever affects timing. Needs to be proper radius and smooth. Believe it or not, the trigger frame is a BIG factor in timing!!! All registered sear packs are semi packs made by modifing FA packs. Some people were more careful than others where the pivot hole was drilled. Take a perfectly timed gun and replace the trigger group frame that all the goodies mount in and it may no longer work! You might as well learn to inspect and repair your own timing because parts DO wear and break!

Remove barrel. Saw off cocking tube flush with receiver. Turn barrel to fit inside of site. Shorten as desired. (Obey the law!!) Original brake is 15-1 RH thread. (Yea, a metric SPECIAL!!) (Die available at Dyna Systems, $48.) Reinstall barrel. Same pin hole, no headspace issue. (But check anyway!!)Install and align site using laser bore sighter. Pin.

HK-51 bolt carrier is merely shortened 91 carrier. Why lighten? Works fine. Cut off "snout" about 1/4" in front of the front surface of carrier. Trim the hunk you cut off to correct length. Bevel both pieces. Turn brass to easily fit inside of tube. Weld, no need to even file down the weld. Slide out "jig" (brass). Squarely cut spring steel insert to about 5/8" long (you know, the one that WAS in the carrier when you cut it apart!) and push in til it bottoms up front. Overall length of "snout" to rear of carrier is 4.080 inches, I think, will recheck and post.

Cocking tube. Do not have the dimensions handy. Will post later. Cut off tapered part in front and shorten rear of it, reweld. Grind radius in bottom of block that has pin hole for forearm so that it does not touch barrel. Will be paper thin so follow radius of barrel. (Verify MP5 forearm when seated against reciever lines up with pin hole.) Shorten cocking tube at rear, DO NOT try in a lathe! Likely to destroy it. Turn a foot long piece of brass to just slide in the receiver. Turn further at one end so it will just fit in cocking tube, all the way up to the plug. Idea is you are making both an alignment jig and a backer to keep weld from sagging inside tube. Bitch to file or grind away!!

Insert modified cocking tube in site, align with receiver, insert "jig". Center tube, more or less, in site. Weld to reciever. Remove "jig". Mill slot for cocking handle in receiver. "Catch area" can be filed to same shape as original was. From plug to rear of new slot is about same length as in original gun. Length must be adequate to allow bolt carrier to move rearward far enough to reliably cock hammer and place bolt behind next round in mag.

Drill a hole through cocking tube for insertion / removal of #@%^&* pin that holds cocking lever (to be like Vollmer). Easier to just put one hole in top of receiver at appropriate location!!!

The cocking piece needs to be longer. Weld to a length of steel tubing with appropriate ID & OD diminsions. Needs to be reasonably straight so lay in V block to weld. Length is correct when, with bolt LOCKED, and cocking piece full forward against the stop plug there is about .010 clearance.

Disassemble the recoil spring stuff. Use a good tube cutter to shorten as the steel is soft. If too long, pin in cocking piece will hit it when cocking, so assemble WITHOUT spring and test. Don't cut too short or it can cause jamming in operation. Remove the (?)14 coils (?) from spring. Goal is for spring to not solid stack and bind when bolt is at full rearward travel. Leave as much as you can! You may wish to "file 13" the rivets that hold piece in end of recoil tube and instead use split pins (roll pins). Reassemble, insert pins, file smooth and even with tube. (Hold spring back with Visegrip clamped GENTLY! around tube.)

Refinish.

Enjoy.

Worth it to pay a gunsmith, ain't it?!

If you REALLY want to do this, I will post the diminsions. Obey NFA!!

Sorry this is so darn long, but you asked! Hope it helps!!

posted 06-01-2001 22:17               

Well, If the rules have you discouraged and confused... then they are working just as intended, aren't they????

Let's face it, the folks that passed these rules don't really WANT you to have these toys. So anything that they can legislate that makes it harder for you to own them, or discourages and confuses you, works in their favor and just as intended.

The real question to me is WHY can't we have these?

Well, I don't want to get off topic, but it just really pisses me off when I, a law abiding, Tax paying, red blooded american citizen am told by some morons in the "imperial federal government" that I can't have a simple bayonet lug on my rifle ( for example - and we all know there are many )!

How many people have been killed by bayonets in this country lately? Have mass bayonetings really reached such a crisis stage that the government had to step in and tell me that I couldn't have one???? What about the american tradition of INNOCENT until proven guilty???

How much hard earned money, time and effort are we having to spend to change out foreign parts out for US parts in these things and to what end? It's absolutely insane if you ask me!!!

Why not lock up the people who commit crimes whether they use a foreign pocket knife or an ALL US PARTS MADE hk-91 and leave me the hell alone????

Ok, I will get off the soap box now and attempt to lower my blood pressure again....

Again, Sorry for the off topic remarks but reading all of these posts, seeing all the hoops that we are forced to jump through to just to keep things legal just infuriates me!... and for no good rational logicla reason!!

If you really look at it objectively, Law abiding, Tax paying loyal Americans can't have bayonet lugs or short barrels on their guns, but that bastard Clinton can sell out our best missile technology to the communist chinese ( possibly our greatest threat to US security in the future ), all in exchange for ILLEGAL re election funds and no one does a damned thing about that!!!!!

Go figure!

SR-25er

posted 06-03-2001 00:45               

Thanks for the info! Yes, we would love to get the specs, dimensions, and any pics you have on the 51. usp40 has been kind enough to offer these but has been plagued with problems moving (haven't we all?) and will hopefully be able to provide them soon. However, it's understandable when ya' gots to take care of yerself first.

posted 06-03-2001 13:51               

SR-25, you make a valid point, and I guess it didn't take this thread any further off topic than the ever-recurring sbr / fa tangent.

Dogbyte, you're right on.

Now can anybody offer any constructive criticism of mm's mod job, or does everybody agree this is the way the real smiths go about it?

Thanks all!!

High_order1

posted 06-03-2001 15:41               

My tolerances are so tight that I had to send the gun to S&H to get a burst pack installed. I had it clipped and pinned by Terry Dyer and tried to run it and it didn't work. S&H had to releave material off of the housing (plastic) in order to make it fit properly. I could have done this, but Curtis didn't charge me anything for doing the job. I have bought 4 Machine Guns from him in the past year...it was kinda a favor.

posted 06-03-2001 18:32               

quote:

---

Originally posted by Nordic:
I think there's a little confusion over what an NFA weapon is. There are actually different classifications of NFA firearms. If you register a gun as an SBR (which is what I'm doing with my G3KA3) then the only thing you can do is chop the barrel. You still have to abide by the assault weapon ban (no retractable stock or flash surpressor) and you still have to have no more than 10 foreign made parts. If you register the gun as a machinegun then you don't have to deal with either of these restrictions. Of course if you're going the machinegun route you're talking about dropping around $4000 for a registered sear. Remember though, if you have a true HK51 sear gun with the 10" barrel, and decide to have some "full auto" fun with another HK you have by swapping lowers, you CANNOT put the semi trigger pack from the other gun on the 51 or you will be making an unregistered SBR! The only other way to beat the assault weapon ban and 10 parts restrictions without doing the sear gun thing is to start out with a preban gun. Now that everything's as clear as mud, good luck!!!

---

I cant retreive that letter now but I did find where James Bardwell mentions it in his NFA FAQ "Section 922(r) does not cover weapons subject to the National Firearms Act, if you register a weapon as a short barreled rifle, for example, you may assemble it out of all imported parts"

He also has a letter here: http://www.cs.cmu.edu/afs/cs/user/wbardwel/public/nfalist/atf_letter3.txt
It is not as easy to understand as the other letters I have seen, but it does mention the same thing, NFA Firearms are not subject to section 922(r).

posted 06-04-2001 16:14               

usp, I dunno. If you get four opinions, and they are all within a few tics of each other, then it seems it would follow that the idea is sound. OTOH, you get one set of measurements, and three others that are different from the first, but close to each other, I'd go with the three. Not gonna cut exactly, just looking for independent corroboration before I take anything I read to heart, yanno??

posted 06-04-2001 16:31               

9.540 - end of recoil spring TUBE to flat surface inside stock, where other end of spring rests. Not including tapered part in end of tube. Replace rivets with 3/32 "tension pins" $.13 each at hardware store. Grind or file flush with tube so spring doesn't catch. Tube length MUST allow cocking handle to travel all the way to back of slot in receiver. Do this last, after building cocking piece and bolt carrier.

4.080 - overall length of bolt carrier. Weld is .250 out from bolt carrier body.

.725 - length of spring sleeve inside snout of carrier. MUST be flat, square and tapered slightly on inside on rear end so will not catch on recoil spring guide.

5.660 - length of cocking slot from rear of plug that serves as front stop for cocking piece to rear of slot.

4.422 - overall length of cocking piece. I made an extension by turning 3/4" OD x 1/8" wall DOM tubing to .700 and welding to original cocking piece. Trim to provide .010 between "snout" and cocking piece when bolt is locked. Do this after bolt carrier is done and cocking tube is installed in receiver.

5.18 - Cenertline of forearm push pin hole to front of trunnion. Check YOUR MP5 forearm fit on this.

4.200 - length of larger portion of cocking tube.

7.250 - tip of barrel to trunnion

5.610 - REAR of front site to front of trunnion.

(Add 1.176 if you want to measure from chamber end of barrel.)

OD to turn barrel for site should be based on ID of site used - they vary a little. A new barrel I have measures .643, yet a used site measures .651!!!!

Use 4 flute end mill to make hole for site pin - doesn't walk like a drill bit may. Ream to size.

Modify front site sleeve - remove bipod part that extends from rear of site. There is only room for thickness of site!

15-1 RH metric thread measures .585 over threads. Don't even THINK about a set screw brake!!!!

The cocking tube is a pain to do! Can't readily turn it in a lathe as it is thin and got that darn slot. 7/8 OD steel tube, .065 wall will make satisfactory replacement. (Federal arms includes these with some kits.) Looks different so not for the purists among you.

Turn to .778 where it goes in front site. .787 x 1.249 long on end to go inside receiver. Don't bother if you plan to butt weld to old tube in receiver. Grind groove for forearm pin. Taper entrance to thin edge. Cut cocking slot on mill - after turned and welded in - .204 wide. Hand form the "latch open" area at rear of cocking slot, as required, with file.

If you look at left side of receiver, there is a rib. (One that claw mount grips bottom of.) Top edge of that rib is top edge of cocking slot viewing from the side.

DON'T forget to drill hole to disassemble cocking piece!! .214 diameter in top of receiver that registers with cocking piece/handle. Try 2.340 back from front of receiver.

Jig pin for bolt carrier. Brass, .518 x 5" long.

Jig pin for cocking tube. Brass, .790 x 16" long. Turn front end to .738 for .520 long. Customize to fit your receiver and cocking tube if you wish. Not so tight you can't remove it!! Not so loose your weld sags inside or alignment suffers.

Barrel pin - 5mm x 28mm. McMaster Carr # 91595A427, $21.00 per 50. They have reamers, end mills and all kinds of neat goodies. A bit expensive but good to deal with IMHO.

Point out what I forgot and I will try to get it for you. This was a clone of a Vollmer gun.

Early poster to this thread was Gunplumber who has undoubtedly forgotten more about guns than I will ever know! I understand he does super finish on HK's too!

posted 06-25-2001 14:57               

As it was told to me: the "import" ban and the resulting "ten parts rule" was about "sporting arms."

Since anyhting registered under NFA is not considered "sporting" the parts rule goes out the window.

Sadly I haven't found the import rule and read it myself. Yet.

Jeff