Can anyone tell me what thread size?

[Crispy]

What thread is used on the wiping head end of my rod bayonet?
I finally found a wiping head but it won't screw on to the rod due to the threaded end being mushroomed out by some previous owners abuse.
I have started to clean up the threads with a small triangular jewelers file but think perhapse a die would be better. Comparing the good threads under magnification they just don't appear to be standard.
Could they be 1/4 - 26 Whitworth?
Any clues would be much appreciated.
Thanks,
Chris.

[musketshooter]

Check with S&S firearms. They sell excellent repro ends.

[Dick Hosmer]

Don't know the exact nomenclature, and am not sure that it precisely follows any particular USS (or Whitworth) form, but the 26tpi is correct. Numerous SA screws used that pitch. I THINK it was their interpretation of the screws on the French muskets, on which the earliest US arms were based. Unless the head is really awful, I'd think the file would ultimately do the job - the die will probably not be easy, or economical, to acquire.

[Crispy]

Thank you both. 26 threads per inch it is, that's why I thought Whitworth, but the thread root is sharp and not rounded like Whitworth.
Let me clarify, it's the threads on the rod I'm trying to salvage, the wiping head appears fine.
Dick, you are right in that the file will eventually get the job done, it's just tedious and I thought there might be a short cut.
Thanks again,
Chris B.

[John Sukey]

Until the advent of the 03, the threads were metric.

[randy langford]

Until the advent of the 03, the threads were metric.

And we thought the metric system was a new thing in the United States.

[Dick Hosmer]

I believe the answer is CLOSE to metric, as in 26 tpi being very close (probably closer than they could accurately measure in 1795) to 25.4 tpi. or 1mm pitch.

Or, Joe thought that 26 was 'close enough' to those screws made by Pierre, and just went with it.

And, are not Krag and 1903 guard screws threaded the same?

[Dan Shapiro]

Amazing the consistent nature of the armory system over the years. The butt plate screw of the M1861 being used up to the M1. The use of band springs up to the M1 carbine. It's like those 'old time people' actually knew what they were doing.