Help needed - what is this muzzle thread?

[300_BLK]

Unknown thread on a 300 BLK

Not 5/8x24.

[gadgetman]

Measure the threads only, peak to peak, or trough to trough, not to the shoulder. Do it over the greatest span of threads you can.

[gonetropo]

who's the manufacturer ?

[scotty]

oversized 16x1 ?..........

[300_BLK]

Measure the threads only, peak to peak, or trough to trough, not to the shoulder. Do it over the greatest span of threads you can.

Over the greatest span 11.4 - 12mm

between a thread .90mm

[300_BLK]

who's the manufacturer ?

Bergara but has been shortened and threaded hence it is not the factory 5/8x24

[veitnamcam]

Over the greatest span 11.4 - 12mm

between a thread .90mm

Over how many threads? 12mm over 12 threads would be 16x1 if its not that then could be anything especially if done by a home gamer.

[gadgetman]

Over the greatest span 11.4 - 12mm

between a thread .90mm

Looking at the photo you'd be looking at a bit over 11mm over a bit over 11 threads which would be more like 1mm pitch. I'd guess as @scotty said above.

[300_BLK]

Over how many threads? 12mm over 12 threads would be 16x1 if its not that then could be anything especially if done by a home gamer.

Looking at the photo you'd be looking at a bit over 11mm over a bit over 11 threads which would be more like 1mm pitch. I'd guess as @scotty said above.

12mm over 12 threads so I guess 16x1 is the winner?

[veitnamcam]

12mm over 12 threads so I guess 16x1 is the winner?

Looks like it....in your photo it almost looks like the the thread is tapered? or maybe just a trick of the camera.
Regardless if 11mm=11 threads and 12mm = 12 threads it will be 1mm pitch.

[300_BLK]

Thanks @veitnamcam & @gadgetman

[Tommy]

Looks like it....in your photo it almost looks like the the thread is tapered? or maybe just a trick of the camera.
Regardless if 11mm=11 threads and 12mm = 12 threads it will be 1mm pitch.

Ohhh how classic would pipe threads be on a barrel

[veitnamcam]

Ohhh how classic would pipe threads be on a barrel

If you did it up real tight it would give the muzzle some choke like the flash 22lrs

[DPT]

Id find it interesting that the thread has been changed from 5/8-24 to 16x1, both threads are very very similar in diameter and pitch. It could possibly be an over sized 5/8-24. Who threaded it?

[ZQLewis]

Not trying to complicate things but being in the hydraulic Hose game I find an M16 thread is typically .1 - .2mm under size. So smack on 5/8". and the differance between 24tpi and 1mm pitch is about bugger all, 24tpi would be 1.05mm.
So none of this helps explain a thread OD of 16.2mm
Zq