**(DONE)**My latest creation. 45 ACP goodness! Part two.

[SAF59]

http://i144.photobucket.com/albums/r176/SAF59/Picture029.jpg

[K.O.A.M.]

Beautiful, but you've got to give us some details.

[SAF59]

Originally posted by K.O.A.M.
Beautiful, but you've got to give us some details.


Receiver: Kahr 1927 A1 semi auto
Frame: 1928A1 Full Auto parts kit minus receiver
Barrel: original 1928A1 fluted barrel (12") with Cutts Compensator when Form 1 is approved
Internals: All semi-auto with home-built bolt hold open pawl. Used the original pivot plate, FA rocker and safety rocker
Rear sight: Original Lyman 1928A1
Repo 50 rd. drum
Wood: Dan Block
Special thanks to Forum Member idsubgun without who's help I would still be waiting on fingerprint cards from ATF.


The hardest part of making this gun was the metal prep and the bluing. Original Thompson frames and receivers have very visible machining marks on the exterior. New production semi-auto receivers are machined quite smooth. I had to finish the frame down to 320 to get a near match on smoothness. Given that the frame and receiver were produced nearly 70 years apart the metal composition is different. This made it a royal PITA to blue. And I did blue it myself using a variant of rust bluing called fume bluing. The original parts blued easily compared to the (modern)receiver. I suppose it is the makeup of the metal that caused this.

[dirtyrice]

Sweet. Thompsons are neat guns. I wouldn't mind having an sbr. Uzis and thompsons are the two guns that look cool as hell as an sbr. Love the wood on yours.

Those drums are pretty pricey aren't they?

[101ABN327]

The Tommygun is a blast to shoot! Here are a couple of shots of mine...

AO 1928A1 on a Form 4

http://www.hunt101.com/data/500/medium/Thompson_002.jpg

http://www.hunt101.com/data/500/medium/Thompson_001.jpg

[SAF59]

Originally posted by 101ABN327


AO 1928A1 on a Form 4 :bow:



I have to play make-believe. :cry:

[stimpsonjcat]

Originally posted by SAF59


I have to play make-believe. :cry:

No sir!

Do not hang your head. Yours is a labor of love...keep the faith!

[Colt Vickers]

SAF59 and all,

Just to clear the air, there is no such thing as constructive possession of an SBR. Per federal law, an SBR is a rifle with a barrel length under 16" or OAL or less than 35" (or something close to that, I'm going off the top of my head.) There is no definition of an SBR that is a counterpart to a machine gun's "part or group of parts" from which an MG can be assembled. Therefore, it either is, or isn't. If it's not assembled, it isn't. I've seen other people on this forum fall into the same trap, and just wanted to clear up any misconception.

Take care,
Tom:fal:

[SAF59]

Colt Vickers;

Just trying to clarify:

Is it true that having the short barrel (mounted) on a rifle that has not been approved and registered a criminal offence? It seems simple to me. That by not having the form 1 approval, screwing a barrel on this 1927 for the purpose of displaying photos on this forum makes it an unregistered and illegal SBR (with an irrefutable evidence trail).

[Colt Vickers]

Originally posted by SAF59
Colt Vickers;

Just trying to clarify:

Is it true that having the short barrel (mounted) on a rifle that has not been approved and registered a criminal offence? It seems simple to me. That by not having the form 1 approval, screwing a barrel on this 1927 for the purpose of displaying photos on this forum makes it an unregistered and illegal SBR (with an irrefutable evidence trail).


SAF59,
I believe by screwing the barrel in, you would have assembled a short barrelled rifle. Seems all the requirements have been met. Wouldn't be any different than installing an 11.5" upper on an AR-15 without an approved Form 1. My point was about constructive possession of an SBR by having all the parts to put one together, but not assembled. I have heard many people say this is a crime, but it isn't.

Now, even though having all the parts from which you can assemble an SBR is not defined as a crime (as long as you don't put them together) keep in mind that the decision to charge a person with a crime is up to the individual US Attorney that is assigned to such a case. If he thinks he can convince the judge/jury that what you have is an SBR, he just may try. Bottom line, just because you are right doesn't mean you won't have to deal with a major hassle. It's always best to not even stray into grey areas. Stay clearly in black and white.

And that is a very nice looking Tommy. I'm still planning on making some Hungarian AMD-65 AK SBR's. I have the kits, I have the receivers, I just don't have the time. One of these days...

Take care,
Tom

[USMC 0341]

SAF59,

How did you make the cocking handle? Did you fab that up from scratch or chop up the FA actuator for that knob?

I have a mid-90's Auto Ord 1927 as well as a TSMG barrel and have plans to do something like yours. I'll probably take the short cut and just drill/tap/bolt on a "removeable stock adapter".

There will be a few minor dimensional differences from a real TSMG but I can live with that. Mine will just be a shooter. Your's is a work of art.

[SAF59]

Originally posted by USMC 0341
SAF59,

How did you make the cocking handle? Did you fab that up from scratch or chop up the FA actuator for that knob?

The cocking handle is a drop-in semi-auto part.

Auto Ordnance Parts (http://www.tommygunshop.com/main_t1.asp)

Numrich has them also (http://www.e-gunparts.com/product.asp?chrProductSKU=499550&MC=)

[Rotor]

Originally posted by SAF59


The hardest part of making this gun was the metal prep and the bluing. And I did blue it myself using a variant of rust bluing called fume bluing. \

How about a little more on fume bluing.

Got any pics of the gun in process?

JR

[SAF59]

Originally posted by Rotor
\

How about a little more on fume bluing.

Got any pics of the gun in process?

JR

You know not what you ask.

Pictures first:

http://i144.photobucket.com/albums/r176/SAF59/Picture001.jpg
http://i144.photobucket.com/albums/r176/SAF59/Picture003.jpg
http://i144.photobucket.com/albums/r176/SAF59/Picture004.jpg
http://i144.photobucket.com/albums/r176/SAF59/Picture007.jpg
http://i144.photobucket.com/albums/r176/SAF59/Picture008-1.jpg
http://i144.photobucket.com/albums/r176/SAF59/Picture010.jpg


The process of fume bluing is simple. In fact so simple that anyone can do it without expensive equipment. All that is required is reagent grade nitric acid (70%), reagent grade Hydrochloric Acid (30%), distilled water for boiling, rainwater preferred (don't use tap water), warm air temperature (higher than 80 degrees) and a sealable plastic container. If you can built a hot box using light bulbs, or whatever, that would work well especially well in the winter months. For metal prep and cleaning, mineral spirits, shop towels, and your preference on finish with wet/dry sandpaper. I would not recommend going higher than 400 grit as any mirror finish will be destroyed by the initial rusting cycle. As for myself, it was quite a learning experience as I couldn't find much information and it was trail and error for me.

The process itself is to produce a fume consisting of NHO+HCL+H2O+heat in a closed container that will produce a rust coating on bare, CLEAN steel. This method is very similar to applied liquid rust bluing agents except you don't have to swap on a liquid, but allow the fumes to do the work. If you have done that before then this should look very familiar to you.

DOs/DONTs ( I learned some of these the hard way!)
Do clean your prepped parts very well.

Don't touch metal with fingers/ hands. Use clean shop towels to handle. Avoid rubber gloves unless you are assured they are clean. Use those for handling the acids. NOTE These acids are very strong. Breathing HCL has the full capability of knocking you on your ass, not to mention burning your breathing tract and skin. Nitric acid will discolor your skin to an ugly yellowish brown color. Always use rubber glove and store what you need in small plastic/glass sealable bottles. Use eyedroppers to dispense.

Use seperate small plastic lids for each acid type. Place them in your hot box with parts and cover. For my hot box I used a 2-2.5 cu. ft. plastic storage box drilled for wooden dowels and set outside in the warm summer air.

Do use small amounts of acid. I was able to use only two or three drops of HCL and a doubled amount of NHO in the containers for each cycle. To much acid will be counter productive. If you use a small hot box then use one drop of HCL and two drops of NHO. Too much acid ( and humidity) will PIT your metal so use a small amount like I stated. It is a process that requires patience and don't think that adding more acid will only accelerate the process. It won't. I tried it and ended up having to redo the receiver (see first photo).

Humidity. I had no way of measuring the humidity in the box. If your parts start sweating it is too much and detremental to the process . I live in a dry climate, but those who live in humid climates may not have to add any water as the humidity in the air may be sufficient. I put some water in a plastic cap or used wet shop towels that were wrung out to be just damp.

The FIRST cycle should take about 3 hours. It should produce a fine coat of even rust on the steel. The part is then removed and boiled in distilled water. If you can get rain water use it instead. As the metal is heated in the boiling water, the rust turns black with a velvet like appearence. Once this is achieved the part can be removed and the remaining water on the part especially around inlets, tapped holes, ect needs to blown/shaken off. The heat of the metal from boiling will do most of the work, but don't allow water to become "ponded" in enclosed areas. Once dry, set aside and let cool. Once it is cool enough to handle you can card it. I used degreased 0000 steel wool and vigorously rubbed the black velvet off the parts. What you should end up with is a slightly darker shade of metal. Don't do the carding in your home. The black powder from carding will stain carpets, clothing, flesh, ect. Nasty stuff to clean up!

Repeat the above cycle. I always used fresh acid for each cycle. If you had a good even coat of rust with your first cycle, all preceding cycles will show less and less rust. The second cycle should run about 3 hours but later cycles can run about 5-8 hours. It is something you have to visually judge. I did not always change the water for boiling for each cycle. I changed it when it looked dirty with "globs" of iron oxide accumulating at the bottom.

Here was the problem I encountered with this Thompson. The original parts (produced circa 1942), only needed about four cycles. The modern receiver didn't really take the bluing as easily. It took about ten cycles and when examining an original part and the receiver there is a slight color difference in them. I believe this is a function of the metal composition.

Here was the greatest mystery to me.
I fully expected that after a few cycles that the metal would look like a nice dark bluing you see a many older guns. What you see is a metal that has the color of "gun metal" paint that those who have ever built plastic models may be familiar with. It is not a very dark color even after may cycles. But when you see no more rust is forming, that is your indication that no more cycles are needed.

When the parts are completed hose down liberally with WD-40. Set them aside for a day. Now take the parts wipe them down and apply a very THIN coat of boiled linseed oil. Rub in well with your fingers and the palm of your hand. Let dry for a day or two. Then oil as needed with regular gun oil. This is the process that turns the not so dark metal into a beautiful satin black/blue finish.

http://i144.photobucket.com/albums/r176/SAF59/blue1928.jpg

[Rotor]

Great... Now where am I gonna get rainwater.

I suppose I could order some....

[SAF59]

Originally posted by Rotor
Great... Now where am I gonna get rainwater.

I suppose I could order some....

Fortunately for me, Colorado is having one of the rainiest spring/summers in recorded history. Climate change isn't all bad!:D

[Rotor]

Thanks for the demo. ( you should cross post in gunsmithing)

That looks outstanding!

Are you going to run with the stock recoil springs?


JR

[SAF59]

Originally posted by Rotor

Are you going to run with the stock recoil springs?


JR

I have though about it. I would only do that if I placed buffer at the back of the receiver. I really don't want the bolt slamming the back of the receiver. On my SA M1, I just ordered the extended bolt handle which made it easy to cock with the stiff factory springs.

[USMC 0341]

I had read that the conversion to fit a full-auto lower to a semi-auto upper was a lot of work, basically requiring a milling machine so I skipped on all those 1928 parts kits back when they were cheap. I had also assumed that the semi-auto internals probably wouldn't fit and work in the full-auto lower.

How much work was it to fit them together?

I would say that what you have there is the next best thing to an actual Colt manufactured 1928 TSMG. Really outstanding.

[tophatjones]

Thanks for showing us your latest project and sharing that excellent write up about fume bluing! What is the reason for rain water? Regards

[SAF59]

Originally posted by tophatjones
What is the reason for rain water?

Rain water is very pure water. It has none of the impurities that tap water or even distilled water have. Just don't collect it from a surface that is known to have oils and other nasties. My roof worked fine. I used both distilled and rain water to boil my parts. The rain water was superior in that it always produced a nice dark velvet coating during boiling. Distilled water produced a black to silvery coating during boiling. This gave me the impression that something had gone wrong. It was also harder to card. I don't think in the end it mattered, but seeing as I had trouble with the receiver and had exhuasted my rain water supply I had to use distilled water. I still wonder if it had something to do with that. If you want to do this gather a large supply of rain water and find the smallest boiliing pan or tank that will work. The pan I used is clearly too large.

[Rotor]

Originally posted by SAF59


I have though about it. I would only do that if I placed buffer at the back of the receiver. I really don't want the bolt slamming the back of the receiver. On my SA M1, I just ordered the extended bolt handle which made it easy to cock with the stiff factory springs.

If you are not already over at http://www.machinegunboards.com/forums/ check it out for 1927 tips.

I have not hung out there in a while (since it was machinegunbooks) but it was usually overflowing with the most knowledgeable TSMG folk.

Years ago there was a guy selling reduced weight springs for Khar 1927's. I don't know if they ever caught on or not.

I can't wait to see that when the barrel is on it.


JR

[gunplumber]

very nice tutorial on rust bluing. I've never considered it on "modern" guns, leaving it for 19th century stuff.

[SAF59]

gunplumber
Do you have any tips. Sounds like you have rust blued. Is my assessment about the color of the metal not darkening until it is oiled correct?

[gunplumber]

I went with the "paint on" for the acid and a heat cabinet. Was not satisfied with the results, so I don't feel qualified to analyze yours.

[L Haney]

Originally posted by SAF59
This one is coming along nicely. Sorry for the no barrel photo but the form 1 is sent. I don't want to be jacked by ATF for "constructive intent" for this SBR.



This is so sad. Really. I'm just musing here, but this issue is so wrong on several different levels. Ya'll know what I mean. Just makes me sad, that's all.
Crap, most of us who want to even fool with the paperwork are better risks than most LEO's. Sorry for the interruption,

Lowell

[FAL GRUNT]

Originally posted by SAF59


Fortunately for me, Colorado is having one of the rainiest spring/summers in recorded history. Climate change isn't all bad!:D

Thats because I've been living here the last 10 months. Once I leave you'll go back to your normal dry life. It's a family curse. Broke an 8 year drought in New Mexico one summer. My father, brother, and I spent a week in NM, it rained the entire week. Hadn't rained all year (almost literally).

Where are you at in CO? I'm stuck in Lakewood.

-myers

[SAF59]

Originally posted by FAL GRUNT

Where are you at in CO? I'm stuck in Lakewood.

-myers

North of Golden, northside of North Table Mtn.

[FAL GRUNT]

What little rust bluing I have done holds true to your statement. I have done the chemical process. Boil part in water, heat with torch, apply chemical, boil in water... do this 5-10 times, card off rust, repeat process. Usually the color does not come out until you have boiled the part, cleaned, and oiled it.

I can't tell you why, but, that was my experience. I have not tried putting BLO on it... but that is interesting... I might try it after my next bluing project.

Should be a great looking gun when your finished! If you need any help breaking er' in :) let me know!

-myers

[SAF59]

Done. See top of thread. Sorry, no outdoor photos today as it is only 9 degrees.

[Rotor]

Wow! How about some more close ups posted down here.

JR