Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login
Posted: 4/11/2006 9:34:43 AM EDT
I bought a 1/2 X28 TPI die/hand stock and want to thread my barrel for a Krink. Has anybody ever done this before and if so are there any tricks or pitfalls involved? I am mechanically retarded but want to learn.
Link Posted: 4/11/2006 10:04:24 AM EDT
[Last Edit: 4/11/2006 10:08:46 AM EDT by TheNorm]
I have threaded all kinds of stuff. There are a few pitfalls...

Make sure to use a cutting fluid on the die. In a pinch, use motor oil. They key to good thread making is to cut a little at a time, go slow, and back it out often to clear the metal chips you are creating.

What I mean by "backing out" the die is this: Once the die starts cutting into the barrel, turn it about 1/2 half turn, then back it up about 1/4 turn. Every 2 complete turns or so, back the whole thing off the barrel and clean off the chips. Keep oil on the cutter. What you are doing is making sure it doesn't seize up. You want nice clean threads...

The die should have an adjustment screw. Ideally you would adjust it to make the threads have a large diameter (open up the die), make the first cut. Then you check your muzzle devices to see how they fit. If they are too tight, close the die down and make another cut (the second cut is much faster, you don't have as much backing up...). Keep adjusting the die smaller until you like the fit of your muzzle devices.

As for using the TPI, thread it into the die so that the edge that will face the muzzle is buried about half way into the die. As the die starts cutting, the TPI will bottom out on the muzzle...STOP THERE and back out the whole thing. At that point you should be able to put the die on the muzzle without the TPI and complete it.

Hope this helps...if not ping back in and I'll confuse you more....

Link Posted: 4/11/2006 10:22:41 AM EDT
Excellent info thanks. I wish I would have asked before I started. For some reason I can't get the die to bite and start threading the barrel. All it is doing is chewing up the end of the barrel. I will see if I can get the die to open up like you said and see if that helps. Everything you said makes
perfect sense except I don't understand the TPI thing. I thought TPI meant threads per inch. Am I wrong on that?
Link Posted: 4/11/2006 10:31:12 AM EDT
It could be that you didn't put the TPI (the die alignment tool) deep enough into the die. If you don't, it bottoms out BEFORE the die starts really cutting, and then you get nowhere fast.

Try it and if you don't figure it out I'll post some pics...

Link Posted: 4/11/2006 10:46:32 AM EDT
I don't think I have a die alignment tool. I have the circle shaped die and the stock it fits in. Do I need something else? Sorry if that is a dumb question?
Link Posted: 4/11/2006 12:51:52 PM EDT
I must be doing something wrong, cuz all the die is doing is thinning the barrel. It is taking off chips but there are no threads on the barrel, it is just making the barrel thinner. I think I should just put the gun in my mouth and call it a day
Link Posted: 4/11/2006 1:54:11 PM EDT
[Last Edit: 4/11/2006 1:56:35 PM EDT by TheNorm]
Uh oh.

yeah you can't thread anything correctly without the alignment tool. The alignment tool has a post that goes down the bore and is threaded for the thread on the die.... it lines up the die with the bore center.

Two things may be happening...first the bbl may be too thick for the die to catch, or you just may need the alignment tool so you can put more force on it in the correct direction. Either way you need the alignment tool.

Next thing to do is to measure your barrel diameter and see if it's a good size to thread at 1/2 28. Do you have calipers or a micrometer? Measure it and report, I'll look up the correct diameter for 1/2 28.

ETA: I'm sorry...I used the term "TPI" for the thread alignment tool we are talking about. MY BAD. Sorry to confuse the issue. You are correct, TPI means "Threads per inch". There are a few terms for the thread alignment tool..."TAT" etc... This is confusing enough without me throwing in more jacked up acronyms...sorry...
Link Posted: 4/11/2006 3:15:56 PM EDT
It is .546 inches. I am trying to figure out how to put a picture on here for you to see it
Link Posted: 4/11/2006 4:39:23 PM EDT
Ahhh. I think you have too much material to thread it 1/2 x 28. You MIGHT be able to pull it off if you open up the die to its max and then make 2-3 cuts, adjusting the die tighter each time (this is a long shot, I doubt the die will adjust that far). The thing is you still need the thread alignment tool.

Just to ask, why do you want 1/2 x 28 on an AK? The cool muzzle devices for AKs are all 14mm x 1 left hand, or 24mm. 14mm = approx 0.55 inch, so your .546 bbl would thread up to 14mm just fine.

Link Posted: 4/11/2006 9:09:57 PM EDT
The krink flash suppressor I bought from ADCO is a 1/2 by 28 thread. I guess it doesn't matter anymore. I screwed the whole thing up. Know of any AK doctors that can cut the portion of the barrel (about 3/4") that I screwed up off of my SA 85 and thread the barrel1/2 X28 and attach the Krink I bought? Is that even legal? Thanks for all your help.
Link Posted: 4/11/2006 9:37:28 PM EDT
Condolences....

If it makes you feel any better, among the pile of perfectly good parts I trashed is a brand new, never fired Ruger Mark II receiver I twisted trying to get the bbl off.

I think you will need an AK doc that can pull the barrel, turn the mess down and put a collar on there at the thread you want. Not hard to do, but it will be some work. Gonna be some $$ too.

Link Posted: 4/11/2006 10:16:03 PM EDT
any ideas on who could do something like that? I cant eat, I cant sleep, all I think about is that damn gun...................somebody help me
Link Posted: 4/12/2006 3:47:12 AM EDT
if its an sa 85 it would be cheaper to just replace the barrel

but all is not lost yet

your barrel is to big you should be threading it in 14x1 lh not 1/2x28

you might be bale to thread it still with a 14x1

Link Posted: 4/12/2006 9:26:42 AM EDT
Is it legal to cut the damaged portion off making the barrel less than 16 inches if you permanently install the suppressor to get it back over 16 inches?
Link Posted: 4/12/2006 10:00:09 AM EDT
If you cut the bbl, you have to precision crown it or your accuracy will suck. Avoid cutting the bbl if you don't have to. Most of the Fake cans will be set up for Krink bbls, so too long for your application.

How badly did you jack up the front end? Got a pic?

You are already in deep with the AK gods, might as well come clean with your bretheren here on the board.
Link Posted: 4/12/2006 11:15:22 AM EDT
I will take a pic when I get home. How do you post a picture on this site? So many things I gotta learn.he
Link Posted: 4/12/2006 4:07:45 PM EDT
The damaged part is 9/16"

I can e-mail you a picture, I have one, but have no idea how to get it on this thread.
Top Top