Trying To Understand Parts Kit's

[cocoabill]

I saw a thread a page or two back where a Thomson 1928 parts kit sold for $3k. I was on gunbroker this afternoon and you see torch cut parts kits selling for up towards $2k and then you see a display gun like this http://www.gunbroker.com/Auction/ViewItem.aspx?Item=324457544#PIC for $800 that no one is bidding on, or this one http://www.gunbroker.com/Auction/ViewItem.aspx?Item=324784568#PIC that has a 90% receiver. Help me understand (if the market is understandable) are not the two links shown parts kits that someone put a fake a receiver on? Is the cut upper receiver worth the one or two grand? Seems to me if someone wants to go to jail and complete an upper to make a functioning parts kit they would be better of machining one then try to mess with the cut one, especially the torch cut.

 

I might be willing to pay $5-600 to hang a display on my bar wall so I can say I have the real thing in the safe, but to pay $3K seams nuts. Just sounds like it's $3K you wont have to buy a legal one.

 

Am I missing something?

 

Thanks

Bill

[Z3BigDaddy]

Yes you are... These people only buy readily made guns for one reason.... If you can't figger it out then... I don't know what to tell you.

 

Edit for a BTW:

 

I could rebuild torch cut kit... But I certainly could not even start to machine one out... I don't have the money for equipment or the knowledge.

 

Second edit:

 

I don't think you can buy display guns at your prices these days... But let me know if you got a place that sells $600 display guns.

Edited January 8, 2013 by Z3BigDaddy

[T Hound]

I have to respectfully disagree. I was able to take a Philadelphia Ordnance 80% receiver and drill it out with a

drill press and still include denial "pins" or islands so that it couldn't accept the full-auto bolt and turn it into a semi-auto. Such plans exist on home build sites and others have done pretty much the same thing. There is, of course, the devil in the details but it is doable---otherwise Recon Bob would go out of business except for display guns.

 

My thought on this is that, yes, some people do it because they think it is easier, and if their welding skills are superior then it probably is; but, others do it because they want an "authentically manufactured" Thompson rather than a self-manufactured Thompson. Either way you can get a working semi-auto that is NOT 1/10 of an

inch less high than the TSMG but is instead exactly the same dimensions.

Edited January 15, 2013 by T Hound

[reconbob]

If you go here http://www.weaponsguild.com/forum/index.php?board=105.0 you can see

 

a variety of Thompson semi builds. If that link does not work you might have to join the weaponsguild.net

 

website to get in. (its free - similar to here make a user name and password)

 

Bob

[Z3BigDaddy]

Not worth it... Deleted... Edited January 16, 2013 by Z3BigDaddy

[T Hound]

Well brother, with the exception of liberals, communists, and socialists, it takes all kinds.

But some of us like the process of machining and building.

 

Those who pay big money are doing so for authenticity. If I had that kind of money to blow

then I would too. But then again I wouldn't be living in California either and would be back

in Texas enjoying my TSMG. But the end result is this: If I can't have a real TSMG because

of my circumstances then at least I can have the illusion of having one.

Edited January 16, 2013 by T Hound

[Z3BigDaddy]

Well brother, with the exception of liberals, communists, and socialists, it takes all kinds.

But some of us like the process of machining and building.

 

Those who pay big money are doing so for authenticity. If I had that kind of money to blow

then I would too. But then again I wouldn't be living in California either and would be back

in Texas enjoying my TSMG. But the end result is this: If I can't have a real TSMG because

of my circumstances then at least I can have the illusion of having one.

Sorry but I don't believe that for one moment. Nice lofty sentiments' though... They just want an easily made full auto.

[T Hound]

Sorry but I don't believe that for one moment. Nice lofty sentiments' though... They just want an easily made full auto.

 

Well that's one reason why I didn't buy one of the very cheap demilled FA Thompson receivers. Because

putting denial "pins" in those is an iffy situation. Obviously if you weld one up BEFORE putting the pins in you have committed a felony. That is why you really have to know what you are doing and the requirements before you do a build. It is much safer to just finish the 80% semi-auto receiver yourself and not have to worry about pins. As far as whether it is legal to put denial islands in a 80% receiver --it has already been done by others and submitted to the BATF and a letter of approval returned. I go by THOSE guidelines because I know they are already approved so there is no "easy full auto" there.

 

As far as being "easy" for others to weld up demilled receivers--I disagree. Welding requires skill and to weld something together like these FA receivers is going to end in failure most of the time simply because these cuts are never convenient cuts. And we both know they risk serious prison time if they succeed. But yes, people still do it. Not saying I agree with it.

Edited January 17, 2013 by T Hound

[cocoabill]

I am understanding now, the weaponsguild site was very informative as to what is going on and why these kits are so pricey. I know the post above say some have got BAFT approval on a semi, does anyone have first hand knowledge that this is true? Edited January 18, 2013 by cocoabill

[Lancer]

I am understanding now, the weaponsguild site was very informative as to what is going on and why these kits are so pricey. I know the post above say some have got BAFTA approval on a semi, does anyone have first hand knowledge that this is true?

 

There is a fair amount of discussion here on the board about the Polston Semi-Auto desgn. Here is on link. Do a search, you will find more.

 

http://www.machinegunboards.com/forums/index.php?showtopic=11278&hl=%2Bpolston+%2Bsemi-auto&fromsearch=1

[Z3BigDaddy]

Sorry but I don't believe that for one moment. Nice lofty sentiments' though... They just want an easily made full auto.

 

Well that's one reason why I didn't buy one of the very cheap demilled FA Thompson receivers. Because

putting denial "pins" in those is an iffy situation. Obviously if you weld one up BEFORE putting the pins in you have committed a felony. That is why you really have to know what you are doing and the requirements before you do a build. It is much safer to just finish the 80% semi-auto receiver yourself and not have to worry about pins. As far as whether it is legal to put denial islands in a 80% receiver --it has already been done by others and submitted to the BATF and a letter of approval returned. I go by THOSE guidelines because I know they are already approved so there is no "easy full auto" there.

 

As far as being "easy" for others to weld up demilled receivers--I disagree. Welding requires skill and to weld something together like these FA receivers is going to end in failure most of the time simply because these cuts are never convenient cuts. And we both know they risk serious prison time if they succeed. But yes, people still do it. Not saying I agree with it.

You can do it with tack(sp?) welds with your $50 yard sale Craftsman without too much effort or knowledge... Trust me it ain't rocket science... Ha Ha... Prison time??? yeah right.... That keeps people from playing...

[Joe H]

I am understanding now, the weaponsguild site was very informative as to what is going on and why these kits are so pricey. I know the post above say some have got BAFTA approval on a semi, does anyone have first hand knowledge that this is true?

 

Cocoabill,

 

The only known Approvals are Polston and N/K Kahr. There may be others but they have not been circulated. You do not legally need an Approval letter to build a semi-auto Thompson for yourself, its your call. If you are going to manufacture one common sense dicates that you get one.

 

Polston got one but as far as I know it never went into production.

 

The quote below from Doug Richardson's website about semi-auto Thompsons IMO sums it up pretty well.

 

Thompson Semi-Autos (26 Jan 08):

 

There seems to be a lot of confusion regarding semi-auto versions of Thompson guns. The yearning for a $20 drop-in semi-auto sear that will convert a Thompson into a legal semi-auto is understandable but not realistic. So, I will attempt here to try to explain the factors involved and the choices that are reasonably available.

 

Like it or not and regardless of the ingenious designs you may have for a semi-auto Thompson, we are all stuck with the Government’s design requirements. Of course, there are no fixed specifications set down in law that designers can work to, it is the interpretations and political agenda of bureaucrats that dictate a vague set of requirements that usually are summarized by some statement like “every case is different so we must examine the gun in order to make a judgment” or something like that. However, there does seem to be a pattern that has emerged that we can call the “requirements” and here it is as I understand it:

 

1) A new receiver must be used and if configured as a pistol, must never have had a buttstock style of trigger housing fitted. You can make a pistol into a rifle but you are not allowed to make a pistol out of a rifle.

 

2) The barrel must be 16" long if a buttstock can be fitted unless the gun is registered as a short barrelled rifle. If no buttstock can be fitted and the foregrip is not a vertical type, then it is a pistol and any length barrel can be used. However, if a person makes a pistol out of a parts kit and retains the short barrel, the Government may conclude that the person intended at some future time to install the short barrel and therefore, has an illegal gun.

 

3) The gun must fire from the closed bolt position.

 

4) The bolt face/firing pin arrangement must be such that if the sear is removed from its semi-automatic functioning of re-engaging the firing pin after every shot, the gun will jam on the next cartridge.

 

5) The receiver must have some means built in to it in order to prevent the operation of an original full-auto bolt if installed.

 

6) The trigger housing must not be able to accept a full-auto sear.

 

7) An unmodified full-auto trigger housing must not be able to fit on to the semi-auto receiver.

 

To date there are only two approved designs. The Numrich/Kahr (N/K) and the Polston.

 

 

Contary to 1) above IMO you can build a new semi reciever from a demilled reciever. ATF considers the demilled reciever as scrap steel and not a gun part subject to the limitations T-Hound mentioned above. You cannot build from an unregistered FA reciever.

 

Joe

[T Hound]

Yeah, I have seen tack welds like you're talking about. I wasn't impressed and I

wouldn't want to trust my safety to using such a gun. But tack welds would

certainly be the start of a permanent weld. I never said prison time would stop

people from doing it brother. That's their decision and risk to take. I'd rather

go with mine.

[T Hound]

I am understanding now, the weaponsguild site was very informative as to what is going on and why these kits are so pricey. I know the post above say some have got BAFT approval on a semi, does anyone have first hand knowledge that this is true?

 

Lancer gave a good tip, but the BATF letter I spoke of resides on the Weapons Guild forum and is a THIRD choice or so I thought. But the truth is that the build I was following was similar to the Polston design in that it uses denial "pins" or islands and a full-auto Thompson bolt modified to be semi-auto. So it may very well have been the Polston letter. Polston has, as far as I know, not pursued the manufacture of his design although he had a website. I sent Polston an email a couple of years ago asking if I could order one of his Thompsons and I never heard back from him. So I assumed he was not interested. I later heard a rumor that he sold the design. To who I do not know. But I have not seen it out there on the internet. Maybe at a gun show on the East coast?

 

As for the letter I speak of, I will try to find it tonight and post the url on this thread so you can take a look OR confirm that it WAS the Polston letter.

Edited January 18, 2013 by T Hound

[T Hound]

I am understanding now, the weaponsguild site was very informative as to what is going on and why these kits are so pricey. I know the post above say some have got BAFTA approval on a semi, does anyone have first hand knowledge that this is true?

 

Cocoabill,

 

The only known Approvals are Polston and N/K Kahr. There may be others but they have not been circulated. You do not legally need an Approval letter to build a semi-auto Thompson for yourself, its your call. If you are going to manufacture one common sense dicates that you get one.

 

Polston got one but as far as I know it never went into production.

 

The quote below from Doug Richardson's website about semi-auto Thompsons IMO sums it up pretty well.

 

Thompson Semi-Autos (26 Jan 08):

 

There seems to be a lot of confusion regarding semi-auto versions of Thompson guns. The yearning for a $20 drop-in semi-auto sear that will convert a Thompson into a legal semi-auto is understandable but not realistic. So, I will attempt here to try to explain the factors involved and the choices that are reasonably available.

 

Like it or not and regardless of the ingenious designs you may have for a semi-auto Thompson, we are all stuck with the Government’s design requirements. Of course, there are no fixed specifications set down in law that designers can work to, it is the interpretations and political agenda of bureaucrats that dictate a vague set of requirements that usually are summarized by some statement like “every case is different so we must examine the gun in order to make a judgment” or something like that. However, there does seem to be a pattern that has emerged that we can call the “requirements” and here it is as I understand it:

 

1) A new receiver must be used and if configured as a pistol, must never have had a buttstock style of trigger housing fitted. You can make a pistol into a rifle but you are not allowed to make a pistol out of a rifle.

 

2) The barrel must be 16" long if a buttstock can be fitted unless the gun is registered as a short barrelled rifle. If no buttstock can be fitted and the foregrip is not a vertical type, then it is a pistol and any length barrel can be used. However, if a person makes a pistol out of a parts kit and retains the short barrel, the Government may conclude that the person intended at some future time to install the short barrel and therefore, has an illegal gun.

 

3) The gun must fire from the closed bolt position.

 

4) The bolt face/firing pin arrangement must be such that if the sear is removed from its semi-automatic functioning of re-engaging the firing pin after every shot, the gun will jam on the next cartridge.

 

5) The receiver must have some means built in to it in order to prevent the operation of an original full-auto bolt if installed.

 

6) The trigger housing must not be able to accept a full-auto sear.

 

7) An unmodified full-auto trigger housing must not be able to fit on to the semi-auto receiver.

 

To date there are only two approved designs. The Numrich/Kahr (N/K) and the Polston.

 

 

Contary to 1) above IMO you can build a new semi reciever from a demilled reciever. ATF considers the demilled reciever as scrap steel and not a gun part subject to the limitations T-Hound mentioned above. You cannot build from an unregistered FA reciever.

 

Joe

 

I would only add Joe that they need to be careful to insert denial pins FIRST or they might subject themselves

to accusations of trying to manufacture a full-auto Thompson.

[cocoabill]

I read Polston's patent and he went through a lot of trouble and expense not to do anything with it. That is unless he sold the rights for big bucks in which case the buyer went through a lot of expense not to do anything, (that we know of). The corporation that had the rights SA Ordnance from what I read was a sister and brother in law closed up and is no longer active.

 

If anyone knows what is up with this it would be nice to know, a kit like he envisioned would very popular.

 

Bill

[Bridgeport28A1]

Maybe Kahr bought the rights to the Polston design to be the sole source?

[T Hound]

Unlikely. Given the popularity such a semi-auto would have I would think they would have

already offered it and probably for a premium fee. But I am actually glad this didn't work

out because the idea was to take already existing full-auto parts and machine them into semi-auto parts.

Even if you only own a semi-auto you may very well eventually buy a Full-auto. Best

to keep those full-auto parts in good condition and in circulation. We can always go

to Recon Bob's 80% receivers and trigger frames instead of ruining perfectlly good

full-auto parts. I am sure the full-auto guys here would agree with me.

Edited January 20, 2013 by T Hound

[T Hound]

I read Polston's patent and he went through a lot of trouble and expense not to do anything with it. That is unless he sold the rights for big bucks in which case the buyer went through a lot of expense not to do anything, (that we know of). The corporation that had the rights SA Ordnance from what I read was a sister and brother in law closed up and is no longer active.

 

If anyone knows what is up with this it would be nice to know, a kit like he envisioned would very popular.

 

Bill

My guess is that people didn't want their full-auto parts converted to semi-auto. The Polston patent would be PERFECT for conversion of

full-auto 80% receivers to semi-auto. That is EXACTLY what should have been done with them.

[mp43sniper]

Sorry but I don't believe that for one moment. Nice lofty sentiments' though... They just want an easily made full auto.

 

I've paid LOTS of money for parts kits that I had no intention of building. I have a very late, aj block StG44 marked rifle that was cut, well, let's say more nicely than what would happen today. It can be hung on the wall as-is and the parts alone are worth a lot of money. However the way it was demilled, along with the uber rare StG marking and barrel in the white, make it very valuable at least to me. And I bet the guy that sold it smiled when he cashed my postal money orders.

 

And keep in mind I'm a 07/C2 so I don't need to play games. There is some cool stuff out there that idiots like me will pay big bucks for because it has history and is awesome. I'd shell out good money for a '21 kit just because it is what it is. See that AC in my avatar? It came from the local Sheriff's office. They had it from new back in the day until just a couple years ago. If I could ever afford a transferable Thompson, I'd pay extra for it because I want it more than some other one. That's how I roll - it doesn't have to make sense to anyone but me.

 

Craig

Edited January 20, 2013 by mp43sniper

[T Hound]

Well it certainly takes all kinds brother. Can't argue with that and I wouldn't want to. Ultimately

people love variety and, hell, you being an 07 don't need any of our advice on the issue. But

your opinion is appreciated.

 

T Hound

[cocoabill]

The way I looked at his patent was a kit of replacement parts and a new bolt and upper receiver keep your old full auto parts on the shelf and install the new ones. If I were going to sell a kit based on his patent that's the way I would do it. If the patent owner is out there and doing anything with this, I hope they are listening.

 

Bill

[Joe H]

The way I looked at his patent was a kit of replacement parts and a new bolt and upper receiver keep your old full auto parts on the shelf and install the new ones. If I were going to sell a kit based on his patent that's the way I would do it. If the patent owner is out there and doing anything with this, I hope they are listening.

 

Bill

 

Bill,

 

I was interested in his Thompson when he first set up his website for early orders. As you know none have been available. At that time, as I understood it you sent him your parts kit plus about $2500 and you got your semi thompson. At that time a parts kit was $500-600 and were available. I doubt this arrangement is feasible today. All the parts would have to be new manufacture.

 

If you check Reconbob's posts he gives an interesting insight into the Polston Tommy Semi. Polston has 2 patents but you can built a Semi Thompsom without either. N/K Kahr has been doing it for over 30 years.

 

I you are looking to buy a currently manufactured semi replica Kahr is the only game in town.

 

Joe

[reconbob]

I believe the Polston design is never going to be put into production. The whole

thing was a soap opera. I know because I worked with Polston and supplied SA-Ordnance

with prototype receivers and even quoted on production. Poston - the inventor was no longer

involved. His sister, who "ran" SA-Ordnance and had no knowledge of guns, business, or

manufacturing is no longer involved. Last I heard the main investor - who financed the whole

thing from the beginning and who also has no knowledge

of guns, manufacturing, or the gun business - had taken control of the project and had found

someone to make the gun. But that was over 2 years ago and I am guessing that the project

has fizzled.

Polston is a mechanical genius, but had no knowledge or machines for accurate or production

work. The few guns he

made the parts were mostly hand made and hand fitted using files and a dremel tool. He had

beautiful hand made sketches of all the parts, but no accurate tolerances and specifications

that you would need for production and interchangeable parts.

The design relied on extensive modification of original parts. In some cases this was almost

impossible. For example, the bolt had to be narrower, and have a pocket in the underside for

the hammer, but Thompson bolts are too hard to machine. Plus the sear notches had to be

welded up and re-machined, etc. I could go on and on, but you get the idea. This gun was a

long, long way from being put into production. A true production sample never existed. There

were a couple of hand made guns that needed constant tinkering and fixing but no gun was

(as over 2 years ago) ever made using machine made interchangeable parts.

There is no doubt that Postons gun was really a neat idea. It had the bronze lock and so

did not need the very heavy recoil springs of the WH/Kahr and was a pleasure to handle.

It had a dreadfully hard trigger pull which may have been worked out, but we may never know.

 

Bob

Edited January 20, 2013 by reconbob

[Lancer]

Bob

Great update on the Polston affair. Looks like it will never happen.