Any info regarding the official gauges for heavy sets and/or mirror 4ths would be greatly appreciated!

Good eye! Double checked just now to be sure and it's a wound 20.

Great!

What I find very curious, if that even though the melody tuning is the same in classic and RMR, the gauges seem to be slightly different.

Questions that come to my mind are:

Do the conflicting data come from the same source (e.g. an SE string list)?

Are the dates of origin of conflicting data similar or disparate?

Just a couple of thoughts...

The only "official data" that I consider are those gauges from the document delivered with a new stick. Everything else, like gauges from 3rd party sets, or measured gauges from open packages (even official), I treat carefully.

True that the gauges have evolved throughout the years. In the beginning, there was only one "gauge", which now is now known as light. And in 1994 an official "string gaute-to-pitch guide" was published by Emmett. However, now those gauges have slightly changed, and on top of that, there is medium and heavy gauges.

So in order to compile this list, I used the following hierarchy:

Official set > measured set
Newest list > oldest
Measured official sets (date unknown)
Thirds party sets
Recommendations

For example, an official document from 2023 has priority over one from 2003. Moreover, both have priority over the gauges sent by someone that measured them, but I take this as a very good starting point if there is no other info available, and most of the time this matches the official sets very well. All of this over a third-party set which doesn't specify tuning nor gauge (light, medium, heavy).

Thanks for that detailed & very logical rundown of your hierarchy.

If I might make a suggestion it would be to consider giving each of those levels a code & using that code on your sheet to indicate the provenance of the data for each tuning?

PS. I took a look at Mirrored 4ths light entry on your sheet & I don't think that data is current. I've have a set of those supplied by SE within the last year & the A2 is wound not plain. My digital micrometer thinks it's 18w, but I'm not 100% convinced by the accuracy (it gives 10p for the D3 & 25w for the E2).

Funny thing, looks I've got a wrong paper included -
got the RMR paper for my MR Railboard stick produced in 2020

Interesting, but still helpful!

I sort of have that on the way...

Bold: official confirmed set.
Bold-italics: gauges to pitches from official list (90s...).
Italics: estimation from other sets and gauges.


Could be, all the missing LIGHT sets have been filled from a pitch-gauges sheets from the 90s... It matched in most of the cases, but I do see some discrepancies as the ones you just pointed out

You could use google docs to share that spreadsheet. It would be easier to follow updates than reviewing forum attachments.