Left hand thread

[Ganderite]

I have a 30 cal muzzle brake intended for the AK. it is a 14mm left hand thread. Would it be a special challenge to thread the barrel of my 303 carbine to take this brake? The barrel is fat enough.

 

[Giblet]

If it is done on a lathe, there is nect to no difference doing LH thread rather than RH. If you need a die sometimes LH can be hard to find, but they are available.

 

[guntech]

It would be a challenge if the lathe does not thread metric.

 

[Suputin]

Metric threads are a PIA on many lathes.

 

[Giblet]

It would be a challenge if the lathe does not thread metric.

True, didn't think of that.

 

[Al Flipo]

Metric threads are a PIA on many lathes.

Why would that be..? With a set of metric transposing gears (100 127) you can cut most metric treads on any lathe equipped with a lead screw.
I believe the muzzle brake in question has a 1 mm pitch, not all that hard to do.

 

[SND]

Just gotta leave the half nut engaged, most lathes lose track if threading in metric, making some lathes and situations sometimes a bit harder than they could otherwise be, but there's always a way.

 

[Ian Robertson]

Hi Jim, I can do it for you, Cheers, Ian Robertson.

 

[Ganderite]

Thanks guys. That will be the last step of the project.

 

[Suputin]

Just gotta leave the half nut engaged, most lathes lose track if threading in metric, making some lathes and situations sometimes a bit harder than they could otherwise be, but there's always a way.

Ed Zachary. Just try cutting threads without disengaging the half nuts. Not as easy as it sounds and a high potential for disaster if it goes wrong. Hit the shoulder with the tooling and you can break all kinds of things.

 

[Jmiverson]

Suputin, you indeed have a great point. But it's very true, don't disengage the half nut cutting metric threads. A sure way to split your threads as any lathe is likely to loose track somewhere within the conversion from imperial to metric. An undercut is necessary when using a manual lathe, most metric threads are left for CNC machines these days.