A question involving redneck engineering and Gatling guns.

[Officers'Wife]

After getting brave I once more went through my uncle's workshop and found a set of drawings for a Gatling style gun with two circles of barrels (one inside the other) turned by the same crank. In the margin was written "not worth the expense of getting the permission of the Great White Father in the NFA" which I took to mean would fall under the National Firearms Act.

How would a Gatling be "OK" but not the modified with the second battery? The design does not call for a motor drive. What am I missing?

 

[F-111 John]

Without seeing the design, it's hard to say. But the NFA regulation for a machine gun is more than one shot with one action of the trigger. Do the inner and outer barrels fire simultaneously?

 

[CapnMac]

A "new" design might be construed as not an exempted Curio.
But, many people assume more of NFA than the Act actually entails.

However, I see a technical issue with the idea--how to feed amoo to the inner ring of barrels. Short of offsetting the inner rimg back far enough to clear the ammo feed, I'm not sure how you'd work it.

 

[H&R Glock]

crank operated is not a machine gun........

 

[Frank Ettin]

crank operated is not a machine gun........

It's nice that you think so, and you might be right.

But when the downside if you're wrong involves up to ten years in federal prison and/or up to a $250,000 fine (plus a lifetime loss of gun rights), you need to be able to backup your guess with legal authority.

And even if ATF has opined that a standard, replica Gatling gun is not a machine gun, that doesn't necessarily mean that the revised design will be as well. Maybe it will be, but someone deserves more reliable information before he bets his freedom on it.

 

[H&R Glock]

26 U.S.C. § 5845(b) For the purposes of the National Firearms Act the term Machinegun means: Any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot without manual reloading, by a single function of the trigger. The frame or receiver of any such weapon.

 

[Frank Ettin]

26 U.S.C. § 5845(b) For the purposes of the National Firearms Act the term Machinegun means: Any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot without manual reloading, by a single function of the trigger. The frame or receiver of any such weapon.

That's nice but hardly resolves the question. See ATF Ruling 2004-5:

...ATF and its predecessor agency, the Internal Revenue Service (IRS), have historically held that the original, crank-operated Gatling Gun, and replicas thereof, are not automatic firearms or machineguns as defined. See Rev. Rul. 55-528, 1955-2 C.B. 482....

But the firearm the OP is asking about would not be a replica of a Gatling gun. It differs from the original design. Would that make a difference? I don't know, and perhaps that's a question a court might need to answer.

Of course the Gatling gun crank operation is different from the minigun considered in the cited ruling, notably by not necessarily having a trigger. But what about the design the OP is interested in. How does that work compared with the classic Gatling gun?

Federal courts have taken a rather broad view of what a "trigger" is. See, for example, U.S. v. Carter, 465 F.3d 658 (6th Cir., 2006), at 665):

...In United States v. Evans, 978 F.2d 1112 (9th Cir.1992), the Ninth Circuit ruled that the lower court's definition of a trigger as "anything that releases the bolt to cause ... (the weapon) to fire" was "consistent with the language of [26 U.S.C. § 5845(b)] and with Congress's intent." 978 F.2d at 1113. Likewise, the reviewing court in United States v. Fleischli, 305 F.3d 643 (7th Cir.2002), rejected the appellant's argument that an electronic switch did not meet the traditional definition of trigger and "join[ed its] sister circuits in holding that a trigger is a mechanism used to initiate a firing sequence." 305 F.3d at 655 (citing Evans, 978 F.2d at 1113-14 n. 2, and United States v. Jokel, 969 F.2d 132, 135 (5th Cir.1992)).

The reasoning adopted by other circuits, as well as simple logic, compels the conclusion that the district court's instruction was proper and not an abuse of discretion. A trigger is generally "anything, as an act or event, that serves as a stimulus and initiates or precipitates a reaction."...

And note that not long ago the ATF ruled that a device called the AutoGlove was subject to the NFA.

So things aren't always as simple as one might like.

 

[hdwhit]

Once the legal question is resolved (or determined to be unresolvable without additional information that is not available), it would be neat to have the moderators move this thread to the General Gun, Gunsmithing or other appropriate forum for a discussion of how the feed mechanism for the concentric barrel bundles could be implemented.

 

[Frank Ettin]

Once the legal question is resolved (or determined to be unresolvable without additional information that is not available), it would be neat to have the moderators move this thread to the General Gun, Gunsmithing or other appropriate forum for a discussion of how the feed mechanism for the concentric barrel bundles could be implemented.

I’ll let this has run a bit longer, in case anyone has some better information. Then I’ll do that if the OP lets me know it’s okay. The design is her intellectual property and might have value. Unless it’s already been patented a public discussion of details would essentially be giving up any protection for those rights she might otherwise have.

 

[milemaker13]

Just based on the standard definition of machine gun, it would depend on whether the inner & outter ring fired together, from one drop of the hammer cam.
Considering the ATF has ruled that the original design is not a machine gun, one might conclude that a newly reimagined design could run out side of that decision... Maybe...

I think setting the inner ring back far enough would allow loading.

 

[Officers'Wife]

Without seeing the design, it's hard to say. But the NFA regulation for a machine gun is more than one shot with one action of the trigger. Do the inner and outer barrels fire simultaneously?

OK, I can't "read" drawings very well but as near as I can determine two barrels are firing together but with a one tooth difference in the cog. According to the notation this amounts to a 1/4 degree turn of the crank. Since each "array(?)" has 12 barrels is it possible there would be questions on the timing?

CapnMac The inner barrels appear to be slightly longer (again, reading drawings isn't my strong suit) but feature(s) a "receiver" that tilts up and the cartridge is pushed from the magazine into the "receiver" at 0 degrees (very top) then is fired at 270 degrees. (I think) Oddly enough the outer barrel fires at 90 degrees.

 

[CapnMac]

I'd like to think that we at THR represent a group reasonably intelligent enough to understand that any mechanism which fired more than one barrel or chamber at a time would likely make the manufacturer "famous" in all of the least desirable ways.

Now, technically, gatling barrel spacing is not happenstance, it's directly related to the lock timing. Otherwise, a person could just make a 9, or 12 barrel, array fitted into the existing geometry.

 

[CapnMac]

CapnMac The inner barrels appear to be slightly longer (again, reading drawings isn't my strong suit) but feature(s) a "receiver" that tilts up and the cartridge is pushed from the magazine into the "receiver" at 0 degrees (very top) then is fired at 270 degrees. (I think) Oddly enough the outer barrel fires at 90 degrees.

Hmm, that might not meet the definition of more than one firing per manipulation (Frank's astute observation above still withstanding).

IIRC, originial Gatlings load at 12 o'clock, and fire at about 5-6 o'clock, so, that would be prototypical.

As above, the lock timing gets complicated in adding barrels. Converting rotary motion into linear motion efficiently takes space, particularly with shells as long as, say, the .45-70 You need camming surfaces, but the angles have to be sorted out so that they do not bind or set up at a disadvantage.

 

[Officers'Wife]

I’ll let this has run a bit longer, in case anyone has some better information. Then I’ll do that if the OP lets me know it’s okay. The design is her intellectual property and might have value. Unless it’s already been patented a public discussion of details would essentially be giving up any protection for those rights she might otherwise have.

Since the man that made the drawings died in 2001 and they were in his "don't pursue" drawer of the file cabinet, even if there was a patent or copyright it would be expired by now. My only curiosity was why he thought the device might fall under the act. Although after reading your first post I now think he decided not to continue out of caution that the "Great White Father" might find the device to fall under the act. Remember this is a man that simply built out of the curiosity to see if they could be built more than designing a product.

 

[Frank Ettin]

Since it looks like there's nothing more to add to the legal discussion, and the OP seems okay with my doing so, I'm moving this to General Discussion.

 

[CapnMac]

why he thought the device might fall under the act

Sadly, that may not be something we can work out.
There are a number of people who feel the Act covers things it does not; and does not cover things that it does. People are individuals and act individually. Sometimes they leave clues in writing or conversations; but, without being privy to those, we are left with naught but speculation.

I do have to admit, the engineering question intrigues me.

Mostly as a way to halve the timing between shots.

Let's say Ring 1 loads at 12 and fires at 6. Ring 2 could load at 1 and fire at 7. With six barrels, either ring fires after a "two hour rotation," so firing "in between" ought not be more than one per trigger action (the second ring having bolts, strikers, etc. of its own), but the rate of fire would be doubled.

Mind, every time I start thinking about this, I keep wandering mentally off on similar variations on the Nordenfeld (another weapon much limited by needing to convert rotary motion in to long-stroke linear motions).

 

[H&R Glock]

I spoke with an atf agent about crank operated "gatling type" guns. He said "If it's got a crank, it ain't a machine gun."
Now if you chose to put a motor or a wind up type spring motor on it, that's different.

 

[Frank Ettin]

I spoke with an atf agent about crank operated "gatling type" guns. He said "If it's got a crank, it ain't a machine gun."....

Completely worthless, even assuming your statement is accurate. First, ATF agents aren’t authorized to render legal opinions. Second, verbal advice from an agent isn’t binding on the agency.

 

[Officers'Wife]

At this point, the legality is somewhat moot. The old gentleman preferred to err on the side of caution and never developed the device.

What I find fascinating, was the drawing of the feed system of the inner barrels. At about 20° a breech would pop up so that at 0° (12 o'clock?) A cartridge would be pushed in then 5° later the breach would drop and twist into a locking lug sort of thingy. It's my guess this system was to get past the interference of the outer barrels.

When my husband read the drawings, he pointed out that the inner barrels revolved counterclockwise and the outer ones clockwise. Unfortunately he is only slightly more skilled at reading drawings than I am. The expert would be a certain unnamed idiot that shall remain my brother and quite frankly… Since he is an idiot I'm not sure of the wisdom of letting him see the drawings.

 

[lysanderxiii]

There is an ATF ruling paper, ATF Rul. 2004-5, dated 2004, that specifically addresses this question. It states that hand cranked Gatling guns are not machine guns because they do not fire automatically.

https://www.atf.gov/file/83561/download

 

[Frank Ettin]

There is an ATF ruling paper, ATF Rul. 2004-5, dated 2004, that specifically addresses this question. It states that hand cranked Gatling guns are not machine guns because they do not fire automatically.....

Yes, we all know about the ruling because I cited and linked to it in post 7. I also quoted the ruling, and it referred to a Gatling gun or replica thereof. The gun in question is not a replica of one of the various variants of the historic Gatling gun, but something different.

I also cited in that post some reasons why the question could be more complicated and why the ATF ruling might not cover the gun design the OP is asking about.

 

[CapnMac]

If I may be forgiven for restating what Frank has already said, but the problem is stark and simple.

Over the course of the history of ATFE, one cannot simply use a "reasonable man" method for presuming what will be, or may be, enforced by said agency. That we must, therefore rely upon only the written rulings of that agency, and from the general to the specific, and not the specific to the general.

Just because one design which uses a crank to engage gears and cams to perform the loading, locking and firing of an individual barrel in a circular array has been approved, does not give reason to imply or infer that any similar design would also be approved.

This flies in the face of logic, and in common life; I might contend that this is why so many seem to disbelieve that it is the case.

 

[CapnMac]

What I find fascinating, was the drawing of the feed system of the inner barrels. At about 20° a breech would pop up so that at 0° (12 o'clock?) A cartridge would be pushed in then 5° later the breach would drop and twist into a locking lug sort of thingy. It's my guess this system was to get past the interference of the outer barrels.

As a creator of such drawings, this continues to pique my interest. Not enough to ask to pour over said drawings (I have quite enough drawings to examine and correct/amend/improve in my 50 hour week as is ).

Now, I considered a contra-rotating design in having the two concentric arrays. But, as a mental design exercise, I just can't come up wit ha good reason to add that complexity to the thing. You are not generating enough torque hand cranking to need to relieve that torque. Firing at 12 or 6 o'clock remains the best way to maintain sight alignment without building parallax into it. and 12 o'clock firing is complicated by being very close to where the best ammunition feed ought to be.

(Torque offset is an issue with Nordenfeld guns, as they rack as they fire from left to right across the barrel array.)

There is another way to look at this, in many ways a Gatling is much like a revolver (sort of). So, the putative design would be like a revolver with two cylinders. It can be made to work, the question is how to do so sensibly.

 

[lysanderxiii]

Yes, we all know about the ruling because I cited and linked to it in post 7. I also quoted the ruling, and it referred to a Gatling gun or replica thereof. The gun in question is not a replica of one of the various variants of the historic Gatling gun, but something different.

I also cited in that post some reasons why the question could be more complicated and why the ATF ruling might not cover the gun design the OP is asking about.

Only an M134 referenced in the paper is not the same design as a "historic Gatling gun", other than the fact that it is a rotary gun. There are many fundamental differences.

Similarly, the many .22 LR designs floating around are also, not the same design as the "historic Gatling gun".

The key word is "automatically", by the ruling paper, manually powered guns are not "automatically firing."

Anyone remember the little crank handles that clipped to the trigger guard?

 

[Frank Ettin]

...The key word is "automatically", by the ruling paper, manually powered guns are not "automatically firing."....

Cite legal authority supporting your opinion regarding the definition of "automatically firing." See the federal court of appeals decision and the later ruling on the Autoglove.

Your's is a reasonable interpretation, but there is no guarantee, based on court decision, that it would be accepted.