Can a semi-auto Thompson be converted?

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hoghunting

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I have been a member of this forum for a few years, but this is my first visit to this category.

I have a semi-auto Thompson that is over 50 years old - it was my grandfather's. Is it legally possible to convert it to fully auto? If so, do I contact the ATF for all the legal requirements?

Thank you for your time and responses.
 
An FFL/SOT class 2 can do it legally. But it can not be transferred to anyone else without an FFL/SOT.

Ranb
 
No. Since 1986 the National Firearms Act registry has been closed to new machine gun registrations. That means that it is unlawful for any new machine guns to be made by non-licensed individuals -- and no new machine guns made by licensees may be transferred to a private individual.

Absolutely no way around that short of becoming a Federal Firearms License holder and "Special Occupational Taxpayer -- Class 02, Manufacturer." If you did have the license and SOT status, you could modify the Thompson and create a "post-86 dealer sample" machine gun.

Those aren't things you can do as a hobby or to produce a one-off conversion. Those licenses are for folks who will be in the business.
 
The other members covered whether or not you could convert a semi-auto Thompson to full-auto. (In short, NO)

However, you *might* have a legal problem with your semi-auto Thompson already, depending on exactly what you have.

You state it's "over 50 years old". Are you SURE of that?

The first semi-auto Thompsons were made in 1926. These "Model of 1927" guns were essentially machine guns with some parts removed so they'd fire semi-auto only. The receivers were the same.

Unfortunately, today these original guns are considered to be machine guns by the ATF, since they use the same MG receiver and can be switched back. (These are the only semi-auto Thompsons made over 50 years ago)

http://www.1927a1.com/

There were less then 50 of these made. If this is what you have, it is rare, but unless it is already registered as a MG with the ATF, it is contraband and not legal to own.

It is more likely that you have one of the more recent semi-auto Thompsons that were first produced starting in 1975. That's not 35 years ago, not 50 though. That's why I asked if you were sure of the age.

Check the barrel length: If your gun has a 10" barrel, you may have a problem. It sounds like you do have either one of the those 50 semi-auto guns that are now considered MG's, or a flat out MG.

If the barrel length is 16", then you have a modern semi-auto version, and all is well.
 
Actually, you can make your semi-auto Thompson into full-auto. You just need to buy one of the very few registered sears (like this one: http://westernfirearms.com/wfc/thompson?set=11) which you can then insert into your gun to make it full auto. Apparently they require some gunsmithing to work properly. Since the sear itself is legally a firearm no new machine gun has been created and there's no 922(o) violation. It'll be almost as expensive to buy one of these as a factory full-auto Thompson though, so it's not like this is some secret cheap shortcut.
 
Thank you for all the information and your time in responding. The Thompson will stay just like it is.

Trebor, the firearm is kept at the family ranch, and has been years since I took it out of the safe. I will check it next time there. Thank you.
 
The original "Model 1927" was just a Model 1921 that had the "Thompson Submachine Gun" stamp milled out and the upper receiver restamped as "Thompson Semi-Automatic Carbine" with the "Full Auto - Single" selector switch in the lower trigger frame replaced with a solid plug that only allowed semi-auto. (Most police departments who had them actually swapped out the fire control groups and converted their semi-auto carbines back to submachine guns.)

The 1970s Thompson Semi-Automatic Carbine made by AutoOrdnance (Numrich, West Hurley) called the Model 1927A1 is internally completely different from the original Model 1921 and Model 1927 and conversion is not possible in the sense of just swapping out parts.
 
Just happened by this thread while looking for gun safes, and after reading the several last posts, what makes police departments exempt from federal law. Normally I would not question police departments actions, but do now, particularly after what we saw occur in New Orleans during the flood?


And are we to believe that body guards etc.(from reputable firms) for personalities, elected officials and the wealthy, do not have full auto weapons.

I see videos even on youtube of young folks (nearly kids) firing full auto .22s and up. Guess I need to look at the rules and regulations and answer my own questions, lest I make a fool of myself (again :eek:). Thought about maybe they are in another country...but what country is more open about firearms than here...excluding the middle east of course.

Sorry if too far off subject but it seemed like the thread was finished, and I'm new here :D.
 
Just happened by this thread while looking for gun safes, and after reading the several last posts, what makes police departments exempt from federal law.
LE and government exemptions are specifically written into the law. This also applies to state laws and local regulations.

Of course, just because the exemption exists doesn't mean manufacturers have to recognize it.

To the OP - if in fact the Thompson is one of the rare older ones, don't take any action until 1) you've thoroughly searched for paperwork on it, and 2) had an attorney contact the BATFE on your behalf to find out whether it is in fact registered or not. The papers could have been lost over the years, and it would be a shame to destroy a firearm that is in fact legal. There's an excellent thread on ARFCOM detailing the steps to take should one run across a machine gun whose status is unknown.
 
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And are we to believe that body guards etc.(from reputable firms) for personalities, elected officials and the wealthy, do not have full auto weapons.

Elected officials of course have dot gov sponsored security so access to full auto weapons is not a problem.

For private security firms yes, they are using some full auto but in general they are paying through the nose like the rest of us for registered and transferable pre-86 stuff or the bigger firms may also be manufacturers which allows them to have post 86.

All it takes is money.

As for other countries being more open, you'd actually be surprised about that. Many countries that have more restrictive firearm laws in general don't have any problems with full auto or suppressors. They treat them just like any other firearm, and they get whatever restrictions any standard firearm would get in their country.

We're actually more restrictive than many places when it comes to this NFA stuff, especially the whole Hughes mess.
 
IIRC Federal law requires any civilian weapon that has a full auto military counterpart has to be made so a full auto conversion is impossible without ruining the weapon.
 
We need a sticky on converting guns, whether old or new, and maybe touch on finding old full-autos in grandpa's attic that are not registered. The "can I legally convert..." and "can I legally register this..." threads are popping up a little too frequently it seems.

I'd put one together, but I'm about to leave for a 10-day elk/deer hunt here in a few minutes. Maybe when I return.
 
ByTheWay: Kahr Arms who bought Auto-Ordnance from Numrich does advertise SBR short barrel rifle versions of the M1927A1 semi-automatic carbine. These have a 10.5" barrel, require federal registration as a SBR with $200 tax, and differ in appearance from the original Model 1927 by not having any provision for a "Full Auto - Single" selector.
 
These days there are a lot of folks inheriting NFA firearms from veterans with a WWII or Korean bring back with papers from commanding officer; from law enforcement or bank guards or private security who bought a personal SMG when it was legal to do so; and so on. Sometimes it is possible to transfer possession legally to an heir on the NFA registry; sometimes the gun is contraband and must be surrendered. The way to avoid criminal charges or loss of legitimate property is to contact a lawyer familiar with NFA law and by no means try to deceive the ATF.
 
IIRC Federal law requires any civilian weapon that has a full auto military counterpart has to be made so a full auto conversion is impossible without ruining the weapon.

Pretty much true. The BATFE technical branch has approved certain modified/alternate designs for the receivers and various fire control parts of most full-auto firearms so that a new receiver can be produced which is very similar to the original design, and accepts most of the original machine gun parts (barrels, stocks, magazines, bolt, etc.) but which is substantively different in some critical area so that it will not easily accept the original design full-auto control parts, and/or other important pieces.

Examples:

1) Semi-auto Uzis (generally) use a different bolt and have a blocking rail built into their receiver so that the submachine gun bolt won't fit.

2) Semi-auto AKs, AKMs, etc. don't have the third axis pin hole drilled near the mag well to accept the rate-reducer/out-of-battery safety device which enables full-auto fire.

3) Semi-auto HKs use a modified method of attaching the trigger housing that won't accept a full-auto trigger group.

4) Semi-auto FALs don't have a portion of the lower receiver milled out to allow certain parts to fit/operate.

Etc.

Of course there are endless variations -- and then nearly endless work-around adaptations (like Drop-In Auto Sears) which USED to (before 1986) be legal to produce to convert these semi-auto variations into full-auto versions. The ATF tech branch has an opinion (or two) on each -- and any new idea needs to be reviewed by them so as not to be inadvertently violating their interpretation of NFA'34.
 
IIRC Federal law requires any civilian weapon that has a full auto military counterpart has to be made so a full auto conversion is impossible without ruining the weapon.

Cite, please? Only because there are several on the market today that are absurdly easy to convert without any alterations to the receiver. And no, I won't discuss them unless I see a copy of your 07/C2 first.
 
Cite, please?
He's overstated the case, but the underlying principle has truth to it. The BATFE has made it painfully clear that owning most firearms that are only a minor parts-swap away from full-auto fire constitutes owning a machine gun -- whether or not you ever actually set it up to operate as one or not.

(Case in point -- owning an AK with the "3rd hole" drilled = illegal unregistered machine gun.)

Sure, human ingenuity can ALWAYS come up with ways around a mechanical obstacle, and there are guns that can be made to operate as a machine gun (safely or NOT) with anything from a few file strokes to a creatively misplaced paperclip. Doing so would constitute an NFA violation. But ANY semi-auto firearm COULD be converted to fire full-auto given enough creativity and machining skill.

The truth underlying highlander's statement comes from the fact that the BATFE certainly has specified that the legal, approved, semi-auto versions of just about every common select-fire or full-auto military weapon (AK, AR, Uzi, HKs, VZs, Stens, MACs, M1919s, MG-38s/42s, Brens, FALs, M-14s, etc., etc.), are substantively different from their original designs so as to make conversion more involved than simply stripping and reassembling the gun with the original full-auto bits in place.
 
IIRC Federal law requires any civilian weapon that has a full auto military counterpart has to be made so a full auto conversion is impossible without ruining the weapon.

It's not Federal Law, it's ATF "interpretation". The same interpretation that made all 10 inch shoestrings in the USA contraband for 2 years.....
 
The ATF Firearms and Technology Branch says that semi-auto firearms readily convertible to full auto will not be approved for civilian sales, and approval has been revoked (for example, the Spitfire) if later testing shows they can be readily converted.

I suspect that if one could convert a Thompson semi-auto to full auto successfully one would have the equipment and know-how to make Sten-type guns from 1.5" pipe and raw metal. And probably do it easier.
 
The Title II license is either $500 or $1000 a year, which is nothing, you can make a bundle of money with it. A Class 3 dealer's license is also needed, really. These Fed licenses allow you to deal in guns and cans, even if your state does not permit an individual to make or own such items. Converting a Tsmg takes about 1/2 a day, earns you about $5000.
 
The Title II license is either $500 or $1000 a year, which is nothing, you can make a bundle of money with it. A Class 3 dealer's license is also needed, really. These Fed licenses allow you to deal in guns and cans, even if your state does not permit an individual to make or own such items. Converting a Tsmg takes about 1/2 a day, earns you about $5000.
:what:
Right...
 
Let's keep some perspective here. Eddie the accountant or Joe the carpenter isn't going to send off $500 - $1,000 to the BATFE and be all squared away as a SOT02 happily making machine guns in his spare time.

He'll need his Type 07 or 10 FFL which includes rather a lot of entanglements and commitments, to include the necessity of being "in the business" of making and/or dealing in these guns. Obtaining your FFL is not a simple or inexpensive proposition and generally requires business licenses, zoning issues, insurance, and quite a few other important details.

Plus there are pretty important limits -- especially on an 03 dealer.

It isn't a hobbyist's route to fun with machine guns.

There have been some very good discussions here on the subject. Probably worth a search if you think you might consider it.
 
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