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 How do I turn down a barrel by hand?
cockroach  [Member]
3/19/2010 6:59:49 AM EST
I KNOW I can pull/lathe it. But it's not on an AR and it is for project enjoyment.
I have the die to thread it, but it needs to be .5" to thread and its .6" now. How do I turn this monkey down concentrically, by hand?
Vise grips and emery cloth? Is there some sort of hand held pipe cutter/ OD decreaser? What do plumbers do with metal pipes in hard to reach places?

––no "just send it to a smith" or "you need a lathe" responses needed, this is for the enjoyment of a project.
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JustKeepSwimming  [Team Member]
3/19/2010 7:23:48 AM EST
Wow, that's not an easy job even if you have a lathe. I assume you actually want to shoot with this barrel after you worked on it? If so, the answer is, "Yes, send it to a smith."

Sorry.
LedZeppelin  [Member]
3/19/2010 7:26:55 AM EST
No. lol I really don't mean to be a dick, but a lathe is the only way you're going to get what you want. (concentric).

I'm all about doing stuff yourself etc.. but that's really tough to keep concentric without a lathe.
polymorpheous  [Member]
3/19/2010 7:47:12 AM EST
Originally Posted By LedZeppelin:
No. lol I really don't mean to be a dick, but a lathe is the only way you're going to get what you want. (concentric).

I'm all about doing stuff yourself etc.. but that's really toughnearly impossible to keep concentric without a lathe.


this ^

Circuits  [Team Member]
3/19/2010 8:04:00 AM EST
Originally Posted By cockroach:
––no "just send it to a smith" or "you need a lathe" responses needed, this is for the enjoyment of a project.


Clamp a collar of some sort around the barrel where you want to maintain a shoulder on your cut, and go to work with a metal file and some calipers.

Regular measuring will let you know where you need to remove a little here or there to keep things as concentric to the bore as your calipers are accurate and your hand is steady. You'll probably need to carefully mark where the lands vs grooves are at the crown, in order to properly measure OD in relation to the bore - always measure from within the grooves or from on the lands to be consistent.

You'll be looking to remove .050 from the initial measurements, roughly, to reduce a nominal .600" to .500" OD.

I'd expect you to spend a full day or more with the hand file to get close to your .500" desired final OD.

Finish with a lighter abrasive like emory paper or a really fine file. Thread with a die and alignment tool.

I think you'll find it tedious and unenjoyable, but achievable.
thehouseproduct  [Member]
3/19/2010 8:34:53 AM EST
Is this a pistol or rifle? Maybe you can chuck it in a drill press....
jsteih  [Team Member]
3/19/2010 9:08:03 AM EST

Originally Posted By cockroach:
I KNOW I can pull/lathe it. But it's not on an AR and it is for project enjoyment.
I have the die to thread it, but it needs to be .5" to thread and its .6" now. How do I turn this monkey down concentrically, by hand?
Vise grips and emery cloth? Is there some sort of hand held pipe cutter/ OD decreaser? What do plumbers do with metal pipes in hard to reach places?

––no "just send it to a smith" or "you need a lathe" responses needed, this is for the enjoyment of a project.

This whole tread is WECSOG....

Oh yea "YOU NEED A LATHE"

Send it to ADCO if ya want something done.
cockroach  [Member]
3/19/2010 9:12:42 AM EST
Looks like I'll have to make a tool then. I'm thinking a pipe cutter with a concave file instead of the blade and a brace on the side to thread in a TAT so I will stay at 90* to center bore. I should be able to set this at my shoulder and rotate a few times/tighten, then repeat with caliper measurements in between. I was hoping someone had done it.
cockroach  [Member]
3/19/2010 9:14:16 AM EST
Its a rifle. I thought about putting the barrel through the press stand at 90* to center bore and running the press down on it with something like a hole saw that is slightly smaller than the original bore diameter and repeating until I was there.
mlg123  [Member]
3/19/2010 10:07:23 AM EST
Draw filing is about the only handheld method that will work for full length diameter reduction. For a small spot (say muzzel) you'll have to cross file & use emery cloth (shoe shine).

Lots of potential for waves & flat spots but it can be done. Just look at some of the stuff that is hand made in the middle east.

MLG
helotaxi  [Member]
3/19/2010 11:30:56 AM EST
Considering that just about everything used to be handmade, the skill and patience of the craftsman is going to determine the quality of the outcome. Can it be done? Sure. Can you do it? I don't know. Would it be much easier with the correct tools? HELL YES!
Circuits  [Team Member]
3/19/2010 12:00:46 PM EST
Originally Posted By cockroach:
Looks like I'll have to make a tool then. I'm thinking a pipe cutter with a concave file instead of the blade and a brace on the side to thread in a TAT so I will stay at 90* to center bore. I should be able to set this at my shoulder and rotate a few times/tighten, then repeat with caliper measurements in between. I was hoping someone had done it.


If you're willing to buy/make a tool, then you could get a 1/2" pilot-centered shell mill, replace the pilot with a brass bore-diameter insert for centering, and adapt the shank for your drill press. I doubt you'll be able to muster the cutting force necessary solely by hand.

If you're able to adapt a pipe cutter with a file, as you describe, for your purposes, then more power to ya.
the_great_snag  [Team Member]
3/19/2010 2:20:40 PM EST
Die cutting threads is sacrilege, especially on a rifle barrel.
Gatorhunt  [Team Member]
3/19/2010 3:12:56 PM EST
There is a couple of things I would never attempt on an AR .. and I am a huge do it yourself guy.

1 .. Try to remove or install a barrel extension.
2 .. Try to cut threads into an unthreaded AR barrel.

Best of luck .. if things go wrong and the dremel tool comes out please take photos and post them so others may learn from it.
458winmag  [Team Member]
3/19/2010 4:09:12 PM EST
Are you going to have enough barrel length to get it fixed after this experiment
458
coldbore141  [Team Member]
3/19/2010 4:46:50 PM EST
Beat a wooden dow rod into the chamber with a hammer(or brick) then chuck the dow in to you black and decker cordless drill(have a spare battery charged) get it spinning really fast(maybe center the muzzle on a pencil clamped to something with visegrips(yeah)), then use the file on you handy dandy pocket multi tool and just start hackin at it till you get there

After you have this all #ucked up I will buy it for $20 and fix it ON MY LATHE! LOL

BTW I cut threads for $35(on a lathe)

Click here to save your barrel

Or use your local, please don't try this at home.
coldbore141  [Team Member]
3/19/2010 4:51:18 PM EST
Originally Posted By the_great_snag:
Die cutting threads is sacrilege, especially on a rifle barrel.


^^^^This^^^^

458winmag  [Team Member]
3/19/2010 6:57:39 PM EST
I didn't want to say that.
No, actually I did. End result might be interesting
458
Elwood_Blues  [Member]
3/19/2010 8:40:37 PM EST
Since you asked, and the acceptable responses specifically exclude the right way, I would not touch it.

I would try Coldbore's approach if I had to find a way to do it. Find a way to turn the barrel, and remove metal using a file

Even if you do get the muzzle concentric down to 0.5", it is going to be touch to start that die straight. Single point threading is the way to go....

Good luck.
adhahn  [Member]
3/20/2010 1:39:37 AM EST
It is very doable if you are not looking for perfection and simply doing this for the enjoyment of the project.

You will need a caliper/micrometer or some creative way to measure from either the inside of the bore, or the part of the barrel you are leaving intact. Just use those measurements to stay as concentric as you can. You could for example take a nail or rod that fits snugly into the bore and bend it into a U or J shape with the inside of the U measuring the amount of material you want left between the bore and outside of the barrel. If you are installing a flash hider it doesn’t have to be perfect. If you are doing this for a suppressor that changes the situation.

To turn down a project barrel for something like a flash hider just get your rough measurements, take a grinder to it and get it close. Do your finishing cutting with a hand file. Use your U shaped rod inserted into the bore and turned in a circle to see where you need to remove material to achieve your finial diameter. You don’t need to polish it up with emery cloth or anything fancy since you will be cutting threads onto the damn thing anyway. As long as you start your die straight, slight imperfections with the concentricity will be OK. You’ll just end up with some spots where the threads are not quite as deep as others. When you screw your flash hider on, check to be sure you won’t have bullet strikes. Drill the center hole out a bit if you need to.

As long as you accept that you have for all intents and purposes ruined the barrel for anyone besides yourself, then it’s no big deal. It’s your barrel; if you want to experiment go for it. Nothing wrong with doing a project to satisfy your own curiosity or doing it just for the hell of it.
coldbore141  [Team Member]
3/20/2010 2:37:06 AM EST
God help us all

Do NOT rotate anything in the bore of the barrel unless you intend to use this barrel for a tomato stake

"I didn't want to say that.
No, actually I did. End result might be interesting
458"

well 458 this should produce a good starting point for an SBR, are you in? LOL

Guys don't use a tap and die set(I don't care how good it is) to thread a barrel, It's just not cool?????
240shwag  [Team Member]
3/20/2010 3:13:19 AM EST
This thread is full of fail.

In the time it takes you to do this, you could be working to put more money away for a lathe.
adhahn  [Member]
3/20/2010 3:38:39 AM EST
Originally Posted By coldbore141:
God help us all

Do NOT rotate anything in the bore of the barrel unless you intend to use this barrel for a tomato stake

"I didn't want to say that.
No, actually I did. End result might be interesting
458"

well 458 this should produce a good starting point for an SBR, are you in? LOL

Guys don't use a tap and die set(I don't care how good it is) to thread a barrel, It's just not cool?????


Twisting a rod in the bore of a project barrel a few times isn't going to make or break this sort of project. Besides, it doesn't appear that the OP cares if this thing ends up a tomato stake anyway. He asked for suggestions on how to turn the barrel without the proper tooling. He specificly requested that folks skip the "take it to a gunsmith" type responces, but never the less that is mostly what he has gotten.

Either foks have terrible reading comprehension or they really don't have anything constructive to add so they decide to shit in his post insted.
oldjack  [Team Member]
3/20/2010 3:42:09 AM EST
I guess you could do it by hand. I've seen examples of .45 pistols made by the Viet Cong out of brazed sheet metal and decent quality AK knockoffs done in caves of Pakistan. That said I have a lathe and milling machine but still send a lot of stuff out because there are people who do it better than me! Look at yourself as a pioneer, the early gun makers had to start somewhere.
coldbore141  [Team Member]
3/20/2010 3:48:59 AM EST
Originally Posted By adhahn:
Originally Posted By coldbore141:
God help us all

Do NOT rotate anything in the bore of the barrel unless you intend to use this barrel for a tomato stake

"I didn't want to say that.
No, actually I did. End result might be interesting
458"

well 458 this should produce a good starting point for an SBR, are you in? LOL

Guys don't use a tap and die set(I don't care how good it is) to thread a barrel, It's just not cool?????


Twisting a rod in the bore of a project barrel a few times isn't going to make or break this sort of project. Besides, it doesn't appear that the OP cares if this thing ends up a tomato stake anyway. He asked for suggestions on how to turn the barrel without the proper tooling. He specificly requested that folks skip the "take it to a gunsmith" type responces, but never the less that is mostly what he has gotten.

Either foks have terrible reading comprehension or they really don't have anything constructive to add so they decide to shit in his post insted.


Okay then by all means just take it to the bench grinder, whack the threads in it and be done! What the hell it is just a barrel, who needs it???? we can always throw stones!

I am trying to save the op from making a mistake, I don't think this should be condoned or promoted in any fashion and I am not Shitting on anything.
"Just sayin"

I see a lot of guys on here(and elsewhere) that try this type of work(Die to thread a barrel), I also see a lot of screwed up barrels as the result of said work. Getting the threads true and straight would be lucky at best.
Luck just don't cut it......
Mad-Machinist  [Member]
3/20/2010 4:34:03 AM EST
Originally Posted By coldbore141:
Originally Posted By the_great_snag:
Die cutting threads is sacrilege, especially on a rifle barrel.


^^^^This^^^^



Why is it such a sacrelige???? As a Machinist with 30 years experience I find this attitude rather humorous. I have regularly used a die to cut threads on MANY things including rifle barrels and I dare you to come to my shop and tell me the difference between something I used a die on and something I single pointed. Do I turn down the OD on a lathe....yes...do I under cut to the min diameter at the shoulder...yes....do I use an alignment tool...sure....but I can die cut threads on a muzzle and then screw a flash supressor on the end and turn on the lathe with no more or less runout than if I had single pointed it. On production pieces I often will rough the thread with a single point and then follw with a die.....lots faster on a manual machine....and some of us don't have CNC

If the OP is patient and careful....it can be done with a file.......I'd start by cutting 6 or 8 flats......ANd it isn't that hard to make a file guide, they will allow very accurate filing.....I made one years ago for a decorative piece in a resrtoration that allowed a nearly perfect octagon to be filed. As the man who taught me always said.....it aint the tools...it is the patience and skill of the man using the tools........just my 2 cents.......and it could be done on a drill press with a roto-broach......I also use them to cut o ring grooves in flat surfaces....much easier than trepanning with a single point tool.

Primos  [Member]
3/20/2010 6:09:46 AM EST
Originally Posted By 240shwag:
This thread is full of fail.

In the time it takes you to do this, you could be working to put more money away for a lathe NEW BARREL.


Mad-Machinist  [Member]
3/20/2010 6:35:26 AM EST
Ididn't say anything about the practicality....I merely commented on the proposition that it COULD be done. But I have done some pretty impractical things over the years for several reasons....one....cause someone told me I couldn't.... and two cause I just wanted to do it.......at the moment I'm doing an AR lower out of a solid block of 7075 on a manual mill....just for the hell of it.....

In the intrest of being helpful...if the OP is near Macon Ga.....if he'll drop by the shop...I'll be happy to turn it down and thread it for him .......................
bigdick  [Member]
3/20/2010 8:46:43 AM EST
how in the heck do you people think the first mills and lathes were made ? with a file . of course it can be done by hand , i would start with a bunch of filed flats that are filed to .510 so each flat is cut .045 , then draw file edges and then shoe shine with some emory clothe
CA_TX-Cop  [Life Member]
3/20/2010 9:12:53 AM EST
I did this with a WASR-3 barrel that I wanted to put a flash-hider on.

The barrel itself was already in the gun, and the front sight base gave me a place to stop. The tap I was using for cutting the threads wouldn't it over the end of the barrel, as the barrel was just a little too large to fit in the tap.

I used sand-paper, and the shoe shine method of drawing the sandpaper back and forth and moving it around the barrel after so many passes. Yeah, it wasn't perfectly round when finished, but cutting the threads into it eliminated the need for it to be perfectly round.

It worked for me, just took a lot of elbow grease and patience.
cockroach  [Member]
3/22/2010 5:42:55 PM EST
Thanks for the helpful replies, what few there were. I find it funny that the only guy to really not act like a total pansy is the dude with machinist in his name

My grandfather made many of his own tools for purposes just like this. Its funny how inept we have become as a society where hand tools are grossly primitive and we have evolved past the ingenuity of our grandfathers. The drawback with hand tools is that they rely solely on the skill of the user. I hate the words "I can't" and "it can't be done". I wont tolerate it from my kids and its sad to hear from adults

For everyone else:ITS NOT AN AR BARREL!!! PLEASE RE-READ OP
458winmag  [Team Member]
3/22/2010 6:07:46 PM EST
Originally Posted By cockroach:
Thanks for the helpful replies, what few there were. I find it funny that the only guy to really not act like a total pansy is the dude with machinist in his name

My grandfather made many of his own tools for purposes just like this. Its funny how inept we have become as a society where hand tools are grossly primitive and we have evolved past the ingenuity of our grandfathers. The drawback with hand tools is that they rely solely on the skill of the user. I hate the words "I can't" and "it can't be done". I wont tolerate it from my kids and its sad to hear from adults

For everyone else:ITS NOT AN AR BARREL!!! PLEASE RE-READ OP

No reason to yell.
Knock yourself out.

Why did you ask, in the first place?
458

cockroach  [Member]
3/22/2010 8:06:28 PM EST
Originally Posted By 458winmag:
Originally Posted By cockroach:
Thanks for the helpful replies, what few there were. I find it funny that the only guy to really not act like a total pansy is the dude with machinist in his name

My grandfather made many of his own tools for purposes just like this. Its funny how inept we have become as a society where hand tools are grossly primitive and we have evolved past the ingenuity of our grandfathers. The drawback with hand tools is that they rely solely on the skill of the user. I hate the words "I can't" and "it can't be done". I wont tolerate it from my kids and its sad to hear from adults

For everyone else:ITS NOT AN AR BARREL!!! PLEASE RE-READ OP

No reason to yell.
Knock yourself out.

Why did you ask, in the first place?
458



I thought someone might be able to share some wisdom, not just spew what I specifically asked not to hear and up their post count.
duckmanmark  [Member]
3/23/2010 7:33:49 AM EST
I build specialty tools for a living and have found the best way to grind down a diameter concentrically is to power turn the tool(in this case, the barrel) and hold it to a grinding belt or wheel. So find a way to hook a drill up to the barrel, tape the edge up to where you want to grind, spin the barrel (drill on one end, probably oil the barrel and let it slide in your other hand) gently hold up against a grinding belt. Take your time, don't let it get hot, measure frequently, thread carefully, and be proud you did it yourself.
Dan877  [Member]
3/23/2010 11:24:01 AM EST
I'm guessing that the barrel in question is mounted to a receiver, not just a "free" barrel that could be turned easily, so here's an interesting video with info on building a barrel lathe for < $50. The video's creator says he turned a barrel that was still mounted to a receiver using this set-up. You could probably fix a similar arrangement to accomplish your task.

Youtube: Home made barrel lathe
cockroach  [Member]
3/23/2010 6:36:59 PM EST
Originally Posted By Dan877:
I'm guessing that the barrel in question is mounted to a receiver, not just a "free" barrel that could be turned easily, so here's an interesting video with info on building a barrel lathe for < $50. The video's creator says he turned a barrel that was still mounted to a receiver using this set-up. You could probably fix a similar arrangement to accomplish your task.

Youtube: Home made barrel lathe


I came across that video in my search, but it won't work with my reciever. I could see doing it with a 10/22 or even an AR, but not anything with a gaspiston housing due to center of gravity and centrifugal force.
cockroach  [Member]
3/23/2010 6:38:35 PM EST
Thanks Duckman, I've used that trick before. I call it the "poor man's lathe". But this is not a loose barrel.

ETA specific post reply
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