Barrel threading

[AnotherRound 0]

Working on ideas for my conversion and i was wondering about others' experiences with threading the .223's barrel. I've read about people cutting the sleve off and then threading the barrel underneath with(im assuming) no turning of the barrel required. but i have yet to read any specifics on requirements for 1/2X28(AR threads). if i remember right 1/2" is about 1mm smaller than 14mm. is that gonna be too much difference to thread without turning it down?

thanks in advance folks

[dinzag 31]

1/2x28 is too small without turning it down. 14mm = 0.551" The Saiga 223's have a larger

barrel O.D. than even the 762x39 rifles.

 

You're better off going with 14x1 LH which really is borderline in itself.

Even with a TAT I had a hard time getting the threads started.

 

9/16x24 is a good choice, but it is limited in the availibility of attachments.

 

Another option - A 14x1 - 24mm adapter could be bored out and welded/set screwed to

the barrel, then you can use 24mm attachments.

[Bad Bob 0]

1/2x28 is too small without turning it down. 14mm = 0.551" The Saiga 223's have a larger

barrel O.D. than even the 762x39 rifles.

Definitely true - I had to take a lot of steel off the muzzle before I could get the 1/2x28RH die on there. Happy with the results, but it was more work...

 

You're better off going with 14x1 LH which really is borderline in itself.

Even with a TAT I had a hard time getting the threads started.

 

I went with 1/2x28RH because I had the die and the appropriate US-made muzzle device sitting in the parts box. Everyone's mileage seems to vary, depending on the availability of tools, 'compliance' parts, etc...

 

9/16x24 is a good choice, but it is limited in the availibility of attachments.

 

Another option - A 14x1 - 24mm adapter could be bored out and welded/set screwed to

the barrel, then you can use 24mm attachments.

 

I've had good luck threading a lot of rifles 9/16x24RH (British L1A1) - but there are not many options in muzzle devices with that thread (I didn't need options, so it didn't bother me). 9/16x24LH (Metric FAL) is a little better choice - more options in terms of 'compliant' 30 caliber brakes and flash supressors. 14x1mm is also a good choice, although most of the options are (once again) 30 caliber. As far as adapters go, I'm currently looking for one myself (1/2x28RH, to 14x1LH, for a 30 caliber bolt action I have ;>)...

[AnotherRound 0]

Bad Bob, how did you go about removing the steel to get the die started short of turning it on a lathe? i would very much like to use the 1/2 X 28 threads because i have multiple muzzle devices for it already. but if it is goin to be too much of a PITA i can just get the 14mm die and buy muzzle device.

[Bad Bob 0]

Bad Bob, how did you go about removing the steel to get the die started short of turning it on a lathe? i would very much like to use the 1/2 X 28 threads because i have multiple muzzle devices for it already. but if it is goin to be too much of a PITA i can just get the 14mm die and buy muzzle device.

I used the method described by Gunplumber at FALfiles (AKA, IIRC, Mark Graham, at Arizona Response Systems, a #1 world-class gunsmith). Figure out the diameter that you need to reduce the barrel to, in order to thread (from memory, I think it's .500 inches for threading 1/2"x28, but I would have to check to be sure, and don't trust my memory). Then you start by filing (or grinding) 'flats' on 4 sides of the barrel, at 90 degrees from each other, with a barrel thickness (across the 'flats' - that's from one 'flat' to another) appropriate for the thread you are wanting to cut (again, let's assume .500 inch, IIRC, but you better get someone to check). Then you file or grind the 'corners' on the end of the barrel to form an octogon, and measure across those (a decent dial micrometer is worth having, if you're building firearms, or doing home improvement - check MidwayUSA, that's where I got mine). Then file or grind the 'corners' to form a 16-sided muzzle. (I think you get the picture - you are converting a large circle to a smaller 'near-circle,' by filing or grinding symetrical flats on the side of the large circle.) When you get to 16 flats (or maybe even 8 - but 16 is no problem), you may be able to use your die (and I DEFINITELY recommend a thread-allignment-tool - TAT - if you are threading your own rifle muzzles) to thread the muzzle, without too much effort required to cut off any excess steel. FWIW, and your mileage may vary, I've used this method on at least 6 rifles, with great success. Once again, I DEFINITELY recommend a thread-allignment-tool - TAT - look it up online...

 

;>)

[Bad Bob 0]

If anybody wants, I can try to find my 1990's copy of Gunplumber's (i.e., Arizona Response Sytems': http://www.arizonaresponsesystems.com/ ) FAL 'cookbook,' and quote his instructions for muzzle threading (don't remember if he had any diagrams or not). He posted it free-of-charge on the internet (he really is a great guy, who jump-started the FAL-building WECSOG movement almost by himself, plus he's a world-class gunsmith to boot - I'm happy to say that I met him once, and shook his hand, at a gun show in Arizona! ;>). I think I've got a copy somewhere...

 

;>)

[IndyArms 10,186]

I wouldnt "recommend" a TAT... (Thread Alignment Tool)

 

 

I WOULD ***INSIST*** ON IT!!! Consider it the **** LAW OF BARREL THREADING****

 

DO NOT THREAD A BARREL WITHOUT A TAT!!!!!

 

There... That said... If you do you can have the muzzle not concentric with the muzzle attachment... this can turn into a DANGEROUS condition. I dont think we need to go into more details than that...

 

Just DONT DO IT!