Phoenix Hy Score Query

[steve medlock]

Could anyone please tell me what the silencer thread is please. My pistol is missing the silencer and I would like to make a replica.

I've just spent ages trying to measure it and still not a clue. I would have expected UNC if they used the US tooling but it doesn't seem to match up. So much harder to measure an internal thread than an external one!

Steve.

[WebleyWombler]

Could anyone please tell me what the silencer thread is please. My pistol is missing the silencer and I would like to make a replica.

I've just spent ages trying to measure it and still not a clue. I would have expected UNC if they used the US tooling but it doesn't seem to match up. So much harder to measure an internal thread than an external one!

Steve.

No experience with the Hy-Score but never seen a UNC thread on the muzzle of anything. Usually UNF for airguns and rimfires or UNEF for the bigger powder burners. Can't see it being a Metric fine

[Ragle Jnr]

I'll dig out mine and check with a thread gauge, will take some time to find both! David

Oh, well external dia of thread is ½ inch, but neither my metric or un thread gauges match! It's less than 20 tpi, and coarser than 1.75, angle similar to metric. I reckon 16 tpi, if any one can do Whitworth or BSF that might help. David

[Farsight]

I'll dig out mine and check with a thread gauge, will take some time to find both! David

Oh, well external dia of thread is ½ inch, but neither my metric or un thread gauges match! It's less than 20 tpi, and coarser than 1.75, angle similar to metric. I reckon 16 tpi, if any one can do Whitworth or BSF that might help. David

Do you mean 1.25 ?

[Ragle Jnr]

No, in metric threads the numbers are the distance apart of the top of the threads, so they are closer, finer as the numbers decrease. The coarsest thread in my gauge is 1.75mm, and it's finer than my silencer.
Perhaps an engineer with a set of thread tables can find what it is, given the age of these I suspect whitworth or British standard fine, unless it's a weird American size, given their origin. David

Just googled whitworth threads, 1/2 WW has 16tpi, so try and borrow a bolt or plug tap to check, may still be a different pitch!

[WebleyWombler]

No, in metric threads the numbers are the distance apart of the top of the threads, so they are closer, finer as the numbers decrease. The coarsest thread in my gauge is 1.75mm, and it's finer than my silencer.
Perhaps an engineer with a set of thread tables can find what it is, given the age of these I suspect whitworth or British standard fine, unless it's a weird American size, given their origin. David

Just googled whitworth threads, 1/2 WW has 16tpi, so try and borrow a bolt or plug tap to check, may still be a different pitch!

From what you have written, I'd be looking at 1/4" NPT