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Cutting down a barrel - correct tools? - Printable Version

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Cutting down a barrel - correct tools? - 140DB - 08-16-2015

Talked to you guys about this before, but wanted to make sure I purchase the correct tools for the job.

1. Looking to shorten the barrel on 2 Chinese T56 SKS' to 16.5" (within ATF/NFA legal rules). ATF site shows that the barrel length measurement is taken from the receiver (where the barrel is threaded or pinned in). Is this correct?

2. Planning on doing the cut with an air-tool cutoff wheel. Any pros/con's to cutting this way? I know I can use a hacksaw, but thought it would be way more convenient/quicker to just use the air-tools I have.

3. To get the trued 90 degree cut, planned on using a file to smooth out the rough cut, then using PTG's 90 degree muzzle facing tool with a .300 pilot - would this be the correct pilot size for a 7.62x39 SKS barrel?

http://www.midwayusa.com/product/743874/ptg-interchangeable-pilot-muzzle-90-degree-crowning-cutter-1-diameter?cm_vc=sugv743874


4. Want to do an 11 degree crown. Again using PTG chamfer tool:

http://www.midwayusa.com/product/684575/ptg-11-degree-muzzle-crown-facing-tool-with-30-caliber-and-up-4-pilot-set-300-312-330-366

5. Wanted to thread the barrel to accept an AR style brake/flash hider.

Was originally going to use a 1/2-28 RH die to cut the threads, but another smith explained that the SKS barrel would be too thin to accept this threading and recommended going M14X1 LH or RH. Thoughts on this?

The threading die I'm looking at is this one: http://www.cncwarrior.com/M14-x-1-LH-Die-p/22961.htm

So before I order the tools, just wanted to verify and get some additional thoughts.

TIA!


RE: Cutting down a barrel - correct tools? - David@reddot - 08-17-2015

You are correct about the barrel length measurements. Yes, you can use a cut-off wheel to cut the barrel, just make sure you don't overheat the barrel by tring to go too fast and that you leave enough room to file it and not be too short. Yes, the .300 pilot should work for the muzzle facing tool. I think that chamfer tool should work just fine as it comes with the same size pilot of .300. As for the threading the barrel for a muzzle brake, off the top of my head I don't know if the SKS barrel is too thin for the 1/2-28 threading. But, if you do use the M14 LH threading, that is an AK style threading, not AR, so you should look at AK style muzzle brakes. I think that's about it. Looks like you've got a pretty good handle on what you're doing. Please let us know if you have any more questions.


(08-16-2015, 09:28 AM)140DB Wrote: Talked to you guys about this before, but wanted to make sure I purchase the correct tools for the job.

1. Looking to shorten the barrel on 2 Chinese T56 SKS' to 16.5" (within ATF/NFA legal rules). ATF site shows that the barrel length measurement is taken from the receiver (where the barrel is threaded or pinned in). Is this correct?

2. Planning on doing the cut with an air-tool cutoff wheel. Any pros/con's to cutting this way? I know I can use a hacksaw, but thought it would be way more convenient/quicker to just use the air-tools I have.

3. To get the trued 90 degree cut, planned on using a file to smooth out the rough cut, then using PTG's 90 degree muzzle facing tool with a .300 pilot - would this be the correct pilot size for a 7.62x39 SKS barrel?

http://www.midwayusa.com/product/743874/ptg-interchangeable-pilot-muzzle-90-degree-crowning-cutter-1-diameter?cm_vc=sugv743874


4. Want to do an 11 degree crown. Again using PTG chamfer tool:

http://www.midwayusa.com/product/684575/ptg-11-degree-muzzle-crown-facing-tool-with-30-caliber-and-up-4-pilot-set-300-312-330-366

5. Wanted to thread the barrel to accept an AR style brake/flash hider.

Was originally going to use a 1/2-28 RH die to cut the threads, but another smith explained that the SKS barrel would be too thin to accept this threading and recommended going M14X1 LH or RH. Thoughts on this?

The threading die I'm looking at is this one: http://www.cncwarrior.com/M14-x-1-LH-Die-p/22961.htm

So before I order the tools, just wanted to verify and get some additional thoughts.

TIA!



RE: Cutting down a barrel - correct tools? - BelieveIn308 - 08-17-2015

Brave guy... I think I would want a 'practice' barrel first. I'd be afraid on the first time doing something like that (if I had the equipment) that I would screw it up. Maybe someone has an old worn out one you could try as your first attempt.


RE: Cutting down a barrel - correct tools? - rwhite135 - 08-17-2015

CNC Warrior makes good stuff. That threading die should work well. 14-1 LH threading is the standard for Combloc weapons like the AK and SKS. There are a couple others that work as well. Personally I'd stick with the 14-1 LH threading.


RE: Cutting down a barrel - correct tools? - 140DB - 08-17-2015

(08-17-2015, 03:00 PM)rwhite135 Wrote: CNC Warrior makes good stuff. That threading die should work well. 14-1 LH threading is the standard for Combloc weapons like the AK and SKS. There are a couple others that work as well. Personally I'd stick with the 14-1 LH threading.

Thanks for confirming ! First time trying something like this and wanted to get as much input so that I don't royally screw things up.


RE: Cutting down a barrel - correct tools? - 140DB - 08-17-2015

(08-17-2015, 11:45 AM)David@reddot Wrote: You are correct about the barrel length measurements. Yes, you can use a cut-off wheel to cut the barrel, just make sure you don't overheat the barrel by tring to go too fast and that you leave enough room to file it and not be too short. Yes, the .300 pilot should work for the muzzle facing tool. I think that chamfer tool should work just fine as it comes with the same size pilot of .300. As for the threading the barrel for a muzzle brake, off the top of my head I don't know if the SKS barrel is too thin for the 1/2-28 threading. But, if you do use the M14 LH threading, that is an AK style threading, not AR, so you should look at AK style muzzle brakes. I think that's about it. Looks like you've got a pretty good handle on what you're doing. Please let us know if you have any more questions.

David: Thanks for the tips! Appreciated!


RE: Cutting down a barrel - correct tools? - mikereddot - 08-20-2015

I think it would be great to add a gallery of pics while you are doing it.


RE: Cutting down a barrel - correct tools? - mikereddot - 08-20-2015

(08-17-2015, 02:14 PM)BelieveIn308 Wrote: Brave guy... I think I would want a 'practice' barrel first. I'd be afraid on the first time doing something like that (if I had the equipment) that I would screw it up. Maybe someone has an old worn out one you could try as your first attempt.

Yeah, i wouldn't do this. This is why having David and Tim in my corner make a great asset. Smile


RE: Cutting down a barrel - correct tools? - BelieveIn308 - 08-21-2015

Yep, to me, I'll bring it to an experienced gunsmith first. Besides the idea that I would screw it up, I don't think I would buy the tooling and equipment to do 1 or 2 barrels. I prefer letting a professional handle it.